Editing London Underground (section)

==Infrastructure==
{{Main|London Underground infrastructure}}

===Railway===
As of 2021, the Underground serves 272 [[Underground station|stations]].<ref>{{Cite news|date=20 September 2021|title=Northern Line extension: Two new Tube stations open|language=en-GB|work=BBC News|url=https://www.bbc.com/news/uk-england-london-58621491|access-date=20 September 2021|archive-date=20 September 2021|archive-url=https://web.archive.org/web/20210920073208/https://www.bbc.com/news/uk-england-london-58621491|url-status=live}}</ref><ref>{{Cite news |last=Attwooll |first=Jolyon |url= https://www.telegraph.co.uk/travel/destinations/europe/united-kingdom/england/london/articles/London-Underground-150-fascinating-Tube-facts/ |archive-url= https://ghostarchive.org/archive/20220111/https://www.telegraph.co.uk/travel/destinations/europe/united-kingdom/england/london/articles/London-Underground-150-fascinating-Tube-facts/ |archive-date=11 January 2022 |url-access=subscription |url-status=live |title=150 London Underground facts (including the birth of Jerry Springer in East Finchley station) |date=25 January 2018 |work=The Telegraph |location= London |access-date=28 April 2020}}{{cbignore}}</ref> Sixteen stations (eight on each of the Metropolitan and Central lines) are outside the [[Greater London|London region]], with five of those beyond the [[M25 motorway|M25 London Orbital motorway]] ([[Amersham station|Amersham]], [[Chalfont & Latimer station|Chalfont & Latimer]], [[Chesham tube station|Chesham]], and [[Chorleywood station|Chorleywood]] on the Metropolitan line and [[Epping tube station|Epping]] on the Central).

Of the thirty-two [[London borough]]s, six ([[London Borough of Bexley|Bexley]], [[London Borough of Bromley|Bromley]], [[London Borough of Croydon|Croydon]], [[Royal Borough of Kingston upon Thames|Kingston]], [[London Borough of Lewisham|Lewisham]] and [[London Borough of Sutton|Sutton]]) are not served by the Underground network, while [[London Borough of Hackney|Hackney]] has [[Old Street tube station|Old Street]] (on the Northern line Bank branch) and [[Manor House tube station|Manor House]] (on the Piccadilly line) just inside its boundaries. Lewisham was served by the [[East London line]] (with stations at [[New Cross railway station|New Cross]] and [[New Cross Gate railway station|New Cross Gate]]) until 2010 when the line and the stations were transferred to the London Overground network.<ref>{{Cite news |url=http://news.bbc.co.uk/1/hi/england/london/8620188.stm |title=East London Line opens to public |date=27 April 2010 |newspaper=BBC |access-date=8 June 2016 |archive-date=18 April 2015 |archive-url=https://web.archive.org/web/20150418154822/http://news.bbc.co.uk/2/hi/uk_news/england/london/8620188.stm |url-status=live }}</ref>

{{wide image|London Underground with Greater London map.svg|980px|A geographic London Underground map showing the extent of the current network ([[Amersham station|Amersham]] and [[Chesham tube station|Chesham]] stations, top left, are beyond the extent of the map.)}}

London Underground's eleven lines total {{convert|402|km|mi}} in length,<ref name="Key Facts"/> making it the eleventh [[List of metro systems|longest metro system in the world]]. These are made up of the sub-surface network and the deep-tube lines.<ref name="Key Facts">{{cite web |url=http://www.tfl.gov.uk/corporate/about-tfl/what-we-do/london-underground/facts-and-figures |title=About TfL – What we do – London Underground – Facts & figures |publisher=Transport for London |access-date=17 June 2014 |archive-date=27 September 2014 |archive-url=https://web.archive.org/web/20140927002759/http://www.tfl.gov.uk/corporate/about-tfl/what-we-do/london-underground/facts-and-figures |url-status=live }}</ref>

The [[Circle line (London Underground)|Circle]], [[District line|District]], [[Hammersmith & City line|Hammersmith & City]], and [[Metropolitan line]]s form the sub-surface network, with [[cut-and-cover]] railway tunnels just below the surface and of a similar size to those on British main lines They converged on a bi-directional loop in central London, sharing tracks and stations with each other at various places along their respective routes.

The [[Bakerloo line|Bakerloo]], [[Central line (London Underground)|Central]], [[Jubilee line|Jubilee]], [[Northern line|Northern]], [[Piccadilly line|Piccadilly]], [[Victoria line|Victoria]] and [[Waterloo & City line]]s are deep-level tubes, with smaller trains that run in circular tunnels (''tubes'') with a diameter of about {{convert|11|ft|8|in}}, with one tube for each direction. The seven deep-level lines have the exclusive use of tracks and stations along their routes with the exceptions of the Piccadilly line, which shares track with the District line, between Acton Town and Hanger Lane Junction, and with the Metropolitan line, between Rayners Lane and Uxbridge; and the Bakerloo line, which shares track with [[London Overground]]'s [[Watford DC Line]] for its above-ground section north of Queen's Park.<ref name="map">{{cite web |url=http://cartometro.com/cartes/metro-london/ |archive-url=https://web.archive.org/web/20200728161716/http://cartometro.com/cartes/metro-london/ |url-status=dead |archive-date=28 July 2020 |title=Detailed London Transport Map |access-date=1 December 2012 |work=cartometro.com }}</ref>

Fifty-five per cent of the system runs on the surface. There are {{convert|20|mi}} of sub-surface tunnels and {{convert|93|mi}} of tube tunnels.<ref name="Key Facts" /> Many of the central London Underground stations on deep-level tube routes are higher than the running lines to assist deceleration when arriving and acceleration when departing.{{sfnp|Croome|Jackson|1993|pp=26, 33, 38, 81}} Trains generally run on the left-hand track. In some places, the tunnels are above each other (for example, the Central line east of St Paul's station); or trains run on the right (for example on the Victoria line between Warren Street and King's Cross St. Pancras, to allow [[cross-platform interchange]] with the Northern line at [[Euston tube station|Euston]]).<ref name="map" />{{sfnp|Croome|Jackson|1993|pp=327–328}}

The lines are electrified with a four-rail DC system: a conductor rail between the rails is energised at {{Val|-210|u=V}} and a rail outside the running rails at {{Val|+420|u=V}}, giving a potential difference of {{Val|630|u=V}}. On the sections of line shared with mainline trains, such as the District line from East Putney to Wimbledon and Gunnersbury to Richmond, and the Bakerloo line north of Queen's Park, the centre rail is bonded to the running rails.<ref name="Martin2012">{{cite book |author=Martin, Andrew |title=Underground, Overground: A Passenger's History of the Tube |url=https://books.google.com/books?id=vh3n5WD_YqsC&pg=PT137 |access-date=7 December 2012 |date=26 April 2012 |publisher=Profile Books |isbn=978-1-84765-807-4 |pages=137–138 |location=London |archive-date=19 January 2023 |archive-url=https://web.archive.org/web/20230119080910/https://books.google.com/books?id=vh3n5WD_YqsC&pg=PT137 |url-status=live }}</ref>

The average speed on the Underground is {{convert|20.5|mph|km/h|abbr=on}}.<ref name="150 tube facts" /> Outside the tunnels of central London, many lines' trains tend to travel at over {{convert|40|mph|km/h|abbr=on}} in the suburban and countryside areas. The Metropolitan line can reach speeds of {{convert|62|mph|km/h|abbr=on}}.<ref>{{Cite web|url=https://citymonitor.ai/transport/which-london-underground-line-fastest-3322|title=Which London Underground line is the fastest?|date=18 September 2017|access-date=21 April 2021|archive-date=15 May 2021|archive-url=https://web.archive.org/web/20210515160549/https://citymonitor.ai/transport/which-london-underground-line-fastest-3322|url-status=live}}</ref>

===Lines===

{{redirect-distinguish|Tube line|Tube Lines}}

The London Underground was used for 1.181{{nbsp}}billion journeys in the year 2023{{ndash}}2024.<ref name="tfl-excel"/>

{| class="sortable wikitable small"
|+ London Underground lines
! rowspan="2" | Name
! rowspan="2" class="unsortable" |Map<br>colour<br><ref>{{cite web |url=http://content.tfl.gov.uk/standard-tube-map.pdf |title=Standard Tube Map |work=Transport for London |author=London Underground |access-date=1 December 2017 |archive-date=25 June 2017 |archive-url=https://web.archive.org/web/20170625083557/http://content.tfl.gov.uk/standard-tube-map.pdf |url-status=live }}</ref>
! rowspan="2" {{vertical header|stp=1|va=middle|Opened}}
! rowspan="2" |Type
! colspan="2" |Length
! colspan="2" rowspan="2" class="unsortable" |Termini
! rowspan="2" {{vertical header|stp=1|va=middle|Stations}}
! rowspan="2" class="unsortable" |Depots
! rowspan="2" |Current<br>rolling stock
! rowspan="2" {{vertical header|stp=1|va=middle|Cars per train}}
! rowspan="2" | Average<br>weekday<br>ridership<br>(2017)<ref>{{Cite web|url=https://api-portal.tfl.gov.uk/docs|title=Rolling Origin & Destination Survey (RODS)|access-date=11 April 2019|archive-date=4 November 2019|archive-url=https://web.archive.org/web/20191104003500/https://api-portal.tfl.gov.uk/docs|url-status=dead}}</ref>
! data-sort-type="number" | Trips per year
! Average<br>trips<br>per mile
|-
!km
!mi
! colspan="2" | ×1000 (2016/17)<ref name="Perdata1617">{{cite web |url=https://www.whatdotheyknow.com/request/up_to_date_per_line_london_under#incoming-1109167 |title=Up to date per line London Underground usage statistics |publisher=[[TheyWorkForYou]] |date=29 April 2018 |access-date=29 April 2018 |archive-url=https://web.archive.org/web/20200702135908/https://www.whatdotheyknow.com/request/up_to_date_per_line_london_under#incoming-1109167 |archive-date=2 July 2020 |url-status=dead }}</ref>
|-
| style="text-align:left;" | [[Bakerloo line]]
| style="background:#{{rcr|London Underground|Bakerloo}}; color:white;"|Brown
| 1906
| Deep tube
| {{convert|23.2|km|disp=table}}
| class="small" | {{indented plainlist|
* [[Harrow & Wealdstone station|Harrow & Wealdstone]]
* [[Queen's Park station (England)|Queen's Park]]
* [[Stonebridge Park station|Stonebridge Park]]
}}
| class="small" | {{indented plainlist|
* [[Waterloo tube station|Waterloo]]
* [[Elephant & Castle tube station|Elephant & Castle]]
}}
| style="text-align:right;" | 25
| class="small" | {{indented plainlist|
* Stonebridge Park
* London Road
* Queen's Park
}}
| [[London Underground 1972 Stock|1972 Stock]]
| style="text-align:right;" | 7
| style="text-align:right;" | 401,123
| style="text-align:right;" | 117,000
| style="text-align:right;" | 8,069
|-
| style="text-align:left;" | [[Central line (London Underground)|Central line]]
| style="background:#{{rcr|London Underground|Central}}; color:white;" | Red
| 1900{{efn|Known as the Central London before 1937.{{sfnp|Day|Reed|2010|p=122}}}}
| Deep tube
| {{convert|74.0|km|disp=table}}
| class="small" | {{indented plainlist|
* [[West Ruislip station|West Ruislip]]
* [[Ealing Broadway station|Ealing Broadway]]
* [[Northolt tube station|Northolt]]
* [[White City tube station|White City]]
* [[North Acton tube station|North Acton]]
}}
| class="small" | {{indented plainlist|
* [[Hainault tube station|Hainault]]
* [[Woodford tube station|Woodford]]
* [[Epping tube station|Epping]]
* [[Loughton tube station|Loughton]]
* [[Leytonstone tube station|Leytonstone]]
* [[Newbury Park tube station|Newbury Park]]
}}
| style="text-align:right;" | 49
| class="small" | {{indented plainlist|
* Ruislip
* Hainault
* White City
}}
| [[London Underground 1992 Stock|1992 Stock]]
| style="text-align:right;" | 8
| style="text-align:right;" | 1,021,084
| style="text-align:right;" | 288,800
| style="text-align:right;" | 6,278
|-
| style="text-align:left;" | [[Circle line (London Underground)|Circle line]]
| style="background:#{{rcr|London Underground|Circle}};"|Yellow
| 1871{{efn|The Metropolitan and District railways joint inner circle service started in the shape of a horseshoe, a complete loop was formed in 1884{{sfnp|Horne|2006|pp=13, 24}} and the current spiral in 2009. The line has been referred to as the Circle line at least since 1936 and first appeared separately on the tube map in 1948.{{sfnp|Ovenden|2013|p=220}}}}
| Sub surface
| {{convert|27.2|km|disp=table}}
| class="small" | [[Hammersmith tube station (Circle and Hammersmith & City lines)|Hammersmith]]<br>''(via [[Moorgate station|Moorgate]] and [[Ladbroke Grove tube station|Ladbroke Grove]])''
| class="small" | [[Edgware Road tube station (Circle, District and Hammersmith & City lines)|Edgware Road]]<br>''(via [[Embankment tube station|Embankment]] and [[Notting Hill Gate tube station|Notting Hill Gate]])''
| style="text-align:right;" | 36
| class="small" | Hammersmith
| [[London Underground S7 and S8 Stock|S7 Stock]]<ref name="March Report">{{cite web |url=http://www.tfl.gov.uk/cdn/static/cms/documents/board-20140326-part-1-item05-commissioners-report.pdf |date=26 March 2014 |title=Commissioner's Report |publisher=Transport for London |pages=3–4 |access-date=2 April 2014 |archive-date=10 October 2022 |archive-url=https://ghostarchive.org/archive/20221010/http://www.tfl.gov.uk/cdn/static/cms/documents/board-20140326-part-1-item05-commissioners-report.pdf |url-status=live }}</ref>
| style="text-align:right;" | 7
| style="text-align:right;" | 257,391
| style="text-align:right;" | 73,000
| style="text-align:right;" | 4,294
|-
| style="text-align:left;"|[[District line]]
| style="background:#{{rcr|London Underground|District}}; color:white;"|Green
| 1868
| Sub surface
| {{convert|64.0|km|disp=table}}
| class="small" | {{indented plainlist|
* Ealing Broadway
* [[Kensington (Olympia) station|Kensington (Olympia)]]
* [[Richmond station (London)|Richmond]]
* [[Wimbledon station|Wimbledon]]
}}
| class="small" | {{indented plainlist|
* [[High Street Kensington tube station|High Street Kensington]]
* Edgware Road
* [[Tower Hill tube station|Tower Hill]]
* [[Barking station|Barking]]
* [[Upminster station|Upminster]]
}}
| style="text-align:right;" | 60
| class="small" | {{indented plainlist|
* Upminster
* Ealing Common
* Lillie Bridge
}}
| [[London Underground S7 and S8 Stock|S7 Stock]]<ref name="March Report"/>
| style="text-align:right;" | 7
| style="text-align:right;" | 842,991
| style="text-align:right;" | 226,100
| style="text-align:right;" | 5,652
|-
| style="text-align:left;" |[[Hammersmith & City line]]
| style="background:#{{rcr|London Underground|Hammersmith & City}};"|Pink
| 1864{{efn|Originally a joint Great Western and Metropolitan railways service, the line first appeared separately on the tube map in 1990.{{sfnp|Rose|2007}}}}
| Sub surface
| {{convert|25.5|km|disp=table}}
| class="small" | Hammersmith
| class="small" | {{indented plainlist|
* [[Plaistow tube station|Plaistow]]
* Barking
}}
| style="text-align:right;" | 29
| class="small" | Hammersmith
| [[London Underground S7 and S8 Stock|S7 Stock]]<ref name="March Report"/>
| style="text-align:right;" | 7
| style="text-align:right;" | 231,193
| style="text-align:right;" | 61,000
| style="text-align:right;" | 3,860
|-
| style="text-align:left;"|[[Jubilee line]]
| style="background:#{{rcr|London Underground|Jubilee}}; color:white;"|Grey
| 1979
| Deep tube
| {{convert|36.2|km|disp=table}}
| class="small" | {{indented plainlist|
* [[Stanmore tube station|Stanmore]]
* [[Wembley Park tube station|Wembley Park]]
* [[Willesden Green tube station|Willesden Green]]
}}
| class="small" | {{indented plainlist|
* [[North Greenwich tube station|North Greenwich]]
* [[West Ham station|West Ham]]
* [[Stratford station|Stratford]]
}}
| style="text-align:right;" | 27
| class="small" | {{indented plainlist|
* Neasden
* Stratford Market
}}
| [[London Underground 1996 Stock|1996 Stock]]
| style="text-align:right;" | 7
| style="text-align:right;" | 999,561
| style="text-align:right;" | 280,400
| style="text-align:right;" | 12,462
|-
| style="text-align:left;"|[[Metropolitan line]]
| style="background:#{{rcr|London Underground|Metropolitan}}; color:white;"|Magenta
| 1863
| Sub surface
| {{convert|66.7|km|disp=table}}
| class="small" | {{indented plainlist|
* [[Amersham station|Amersham]]
* [[Chesham tube station|Chesham]]
* [[Uxbridge tube station|Uxbridge]]
* [[Watford tube station|Watford]]
* [[Rickmansworth station|Rickmansworth]]
}}
| class="small" | {{indented plainlist|
* [[Harrow-on-the-Hill station|Harrow-on-the-Hill]]
* Wembley Park
* [[Baker Street tube station|Baker Street]]
* [[Aldgate tube station|Aldgate]]
}}
| style="text-align:right;" | 34
| class="small" | Neasden
| [[London Underground S7 and S8 Stock|S8 Stock]]
| style="text-align:right;" | 8
| style="text-align:right;" | 352,464
| style="text-align:right;" | 80,900
| style="text-align:right;" | 1,926
|-
| style="text-align:left;"|[[Northern line]]
| style="background:#{{rcr|London Underground|Northern}}; color:white;"|Black
| 1890{{efn|The name dates from 1937.{{sfnp|Day|Reed|2010|p=122}}}}
| Deep tube
| {{convert|58.0|km|disp=table}}
| class="small" | {{indented plainlist|
* [[Edgware tube station|Edgware]]
* [[High Barnet tube station|High Barnet]]
* [[Mill Hill East tube station|Mill Hill East]]
* [[Finchley Central tube station|Finchley Central]]
* [[Golders Green tube station|Golders Green]]
}}
| class="small" | {{indented plainlist|
* [[Kennington tube station|Kennington]]
* [[Battersea Power Station tube station|Battersea Power Station]]
* [[Morden tube station|Morden]]
}}
| style="text-align:right;" | 52
| class="small" | {{indented plainlist|
* Edgware
* Golders Green
* Highgate
* Morden
}}
| [[London Underground 1995 Stock|1995 Stock]]
| style="text-align:right;" | 6
| style="text-align:right;" | 1,123,342
| style="text-align:right;" | 294,000
| style="text-align:right;" | 8,166
|-
| style="text-align:left;"|[[Piccadilly line]]
| style="background:#{{rcr|London Underground|Piccadilly}}; color:white;"|Dark blue
| 1906
| Deep tube
| {{convert|71.0|km|disp=table}}
| class="small" | {{indented plainlist|
* [[Cockfosters tube station|Cockfosters]]
* [[Arnos Grove tube station|Arnos Grove]]
* [[Oakwood tube station|Oakwood]]
}}
| class="small" | {{indented plainlist|
* [[Acton Town tube station|Acton Town]]
* [[Heathrow Terminals 2 & 3 tube station|Heathrow Terminals 2 & 3]]
* [[Heathrow Terminal 4 tube station|Heathrow Terminal 4]]
* [[Heathrow Terminal 5 station|Heathrow Terminal 5]]
* [[Northfields tube station|Northfields]]
* [[Rayners Lane tube station|Rayners Lane]]
* Uxbridge
}}<ref>{{Cite web|title=Piccadilly Underground line – Transport for London|url=https://tfl.gov.uk/tube/route/piccadilly/|access-date=17 March 2021|website=Transport for London|language=en-GB|archive-date=26 May 2021|archive-url=https://web.archive.org/web/20210526111846/https://tfl.gov.uk/tube/route/piccadilly/|url-status=live}}</ref>
| style="text-align:right;" | 53
| class="small" | {{indented plainlist|
* Cockfosters
* Northfields
}}
| [[London Underground 1973 Stock|1973 Stock]]
| style="text-align:right;" | 6
| style="text-align:right;" | 710,647
| style="text-align:right;" | 206,900
| style="text-align:right;" | 4,670
|-
| style="text-align:left;"|[[Victoria line]]
| style="background:#{{rcr|London Underground|Victoria}}; color:white;"|Light blue
| 1968
| Deep tube
| {{convert|21.0|km|disp=table}}
| class="small" | {{indented plainlist|
* [[Brixton tube station|Brixton]]
* [[London Victoria station|Victoria]]
}}
| class="small" | {{indented plainlist|
* [[Walthamstow Central station|Walthamstow Central]]
* [[Seven Sisters station|Seven Sisters]]
}}
| style="text-align:right;" | 16
| class="small" | Northumberland Park
| [[London Underground 2009 Stock|2009 Stock]]
| style="text-align:right;" | 8
| style="text-align:right;" | 955,823
| style="text-align:right;" | 263,400
| style="text-align:right;" | 20,261
|-
| style="text-align:left;"|[[Waterloo & City line]]
| style="background:#{{rcr|London Underground|Waterloo & City}}; color:black;"|Turquoise
| 1898{{efn|Until 1994 the Waterloo & City line was operated by British Rail and its predecessors.}}
| Deep tube
| {{convert|2.5|km|disp=table}}
| class="small" | [[Bank and Monument stations|Bank]]
| class="small" | Waterloo
| style="text-align:right;" | 2
| class="small" | Waterloo
| [[London Underground 1992 Stock|1992 Stock]]<ref name="wdtk-lu">{{cite web|last1=Neil|first1=Graham|title=London Underground Rolling Stock Information Sheet|url=https://www.whatdotheyknow.com/cy/request/284276/response/737827/attach/6/RS%20Info%20Sheets%204%20Edition.pdf|website=WhatDoTheyKnow|date=4 August 2015|access-date=17 April 2016|archive-url=https://web.archive.org/web/20160505193100/https://www.whatdotheyknow.com/cy/request/284276/response/737827/attach/6/RS%20Info%20Sheets%204%20Edition.pdf|archive-date=5 May 2016|url-status=live}}</ref>
| style="text-align:right;" | 4
| style="text-align:right;" | 59,492
| style="text-align:right;" | 16,900
| style="text-align:right;" | 11,267
|}
{{notelist}}

{{image frame|align=center|content={{London Underground patronage by line}}|caption=London Underground patronage by line in 2020–21}}

===Services using former and current main lines===
[[File:London Underground full map.svg|thumb|upright=1.35|A map of the entire system with accurate positions of stations but simplified presentation of lines]]
The Underground uses several railways and alignments that were built by main-line railway companies.
;Bakerloo line
:Between [[Queen's Park (London) station|Queen's Park]] and [[Harrow & Wealdstone station|Harrow & Wealdstone]] this runs over the [[Watford DC Line]] also used by [[London Overground]], alongside the [[London & North Western Railway]] (LNWR) main line that opened in 1837. The route was laid out by the LNWR in 1912–15 and is part of the [[Network Rail]] system.
;Central line
:The railway from just south of [[Leyton tube station|Leyton]] to just south of [[Loughton tube station|Loughton]] was built by [[Eastern Counties Railway]] in 1856 on the same alignment in use today.{{sfnp|Brown|2012}} The Underground also uses the line built in 1865 by the [[Great Eastern Railway]] (GER) between Loughton to [[Ongar tube station|Ongar]] via [[Epping tube station|Epping]]. The connection to the main line south of Leyton was closed in 1970 and removed in 1972. The line from Epping to Ongar was closed in 1994; most of the line is in use today by the heritage [[Epping Ongar Railway]].{{sfnp|Brown|2012}} The line between [[Newbury Park tube station|Newbury Park]] and Woodford junction (west of [[Roding Valley tube station|Roding Valley]]) via Hainault was built by the GER in 1903, the connections to the main line south of Newbury Park closing in 1947 (in the Ilford direction) and 1956 (in the Seven Kings direction).{{sfnp|Brown|2012}}
;Central line
:The line from just north of [[White City tube station|White City]] to [[Ealing Broadway tube station|Ealing Broadway]] was built in 1917 by the [[Great Western Railway]] (GWR) and passenger service introduced by the Underground in 1920. [[North Acton tube station|North Acton]] to [[West Ruislip tube station|West Ruislip]] was built by GWR on behalf of the Underground in 1947–8 alongside the pre-existing tracks from Old Oak Common junction towards {{rws|High Wycombe}} and beyond, which date from 1904.{{sfnp|Brown|2012}} {{As of|2013|5}}, the original Old Oak Common junction to {{rws|South Ruislip}} route has one main-line train a day to and from Paddington.<ref>{{NRtimes|May 13|115}}</ref>
;District line
:South of [[Kensington Olympia station|Kensington (Olympia)]] short sections of the 1862 [[West London Railway]] (WLR) and its 1863 West London Extension Railway (WLER) were used when District extended from Earl's Court in 1872. The District had its own bay platform at Olympia built in 1958 along with track on the bed of the 1862–3 WLR/WLER northbound. The southbound WLR/WLER became the new northbound main line at that time, and a new southbound main-line track was built through the site of former goods yard. The 1872 junction closed in 1958, and a further connection to the WLR just south of Olympia closed in 1992. The branch is now segregated.{{sfnp|Brown|2012}}
:The line between Campbell Road junction (now closed), near [[Bromley-by-Bow tube station|Bromley-by-Bow]], and [[Barking station|Barking]] was built by the [[London, Tilbury & Southend Railway]] (LTSR) in 1858. The slow tracks were built 1903–05, when District services were extended from [[Bow Road]] (though there were no District services east of [[East Ham tube station|East Ham]] from 1905 to 1932). The slow tracks were shared with LTSR stopping and goods trains until segregated by 1962, when main-line trains stopped serving intermediate stations.{{sfnp|Brown|2012}}
:The railway from Barking to [[Upminster tube station|Upminster]] was built by LTSR in 1885 and the District extended over the route in 1902. District withdrew between 1905 and 1932, when the route was quadrupled. Main-line trains ceased serving intermediate stations in 1962, and the District line today only uses the 1932 slow tracks.{{sfnp|Brown|2012}}
:The westbound track between east of [[Ravenscourt Park tube station|Ravenscourt Park]] and [[Turnham Green tube station|Turnham Green]] and Turnham Green to Richmond (also used by [[London Overground]]) follows the alignment of a railway built by the [[London & South Western Railway]] (LSWR) in 1869. The eastbound track between Turnham Green and east of Ravenscourt Park follows the alignment built in 1911; this was closed 1916 but was re-used when the Piccadilly line was extended in 1932.{{sfnp|Brown|2012}} The section between Turnham Green and Richmond still belongs to [[Network Rail]] now.<ref name="lu-iwa">Section 10 - Network Rail, London Underground - Individual Working Alone, [https://www.tectraining.co.uk/doc/LU-IWA-Information-Booklet-March-2015.pdf] {{Webarchive|url=https://web.archive.org/web/20230204191151/https://www.tectraining.co.uk/doc/LU-IWA-Information-Booklet-March-2015.pdf|date=4 February 2023}}</ref>
:The line between [[East Putney tube station|East Putney]] and [[Wimbledon station|Wimbledon]] was built by the LSWR in 1889. The last scheduled main-line service ran in 1941{{sfnp|Brown|2012}} but it still sees a few through Waterloo passenger services at the start and end of the daily timetable.<ref>Maund, Richard (2013). [http://www.psul4all.free-online.co.uk/2013.htm Passenger Train Services over Unusual Lines] {{webarchive|url=https://web.archive.org/web/20130701060420/http://www.psul4all.free-online.co.uk/2013.htm |date=1 July 2013 }}.</ref> The route is also used for scheduled ECS movements to/from Wimbledon Park depot and for Waterloo services diverted during disruptions and track closures elsewhere. This section is now owned by London Underground but the signalling is still operated by [[Network Rail]].<ref name="lu-iwa"/>
;Hammersmith & City
:Between [[Paddington tube station (Circle and Hammersmith & City lines)|Paddington]] and [[Westbourne Park tube station|Westbourne Park Underground station]], the line runs alongside the main line. The Great Western main line opened in 1838, serving a temporary terminus the other side of Bishop's Road. When the current Paddington station opened in 1854, the line passed to the south of the old station.{{sfnp|Brown|2012}} On opening in 1864, the Hammersmith & City Railway (then part of the Metropolitan Railway) ran via the main line to a junction at Westbourne Park, until 1867 when two tracks opened to the south of the main line, with a crossing near Westbourne Bridge, Paddington. The current two tracks to the north of the main line and the subway east of Westbourne Park opened in 1878.{{sfnp|Peacock|1970|p=67}} The Hammersmith & City route is now completely segregated from the main line.
;Jubilee line
:The rail route between [[Canning Town station|Canning Town]] and [[Stratford station|Stratford]] was built by the GER in 1846, with passenger services starting in 1847. The original alignment was quadrupled "in stages between 1860 and 1892" for freight services before the extra (western) tracks were lifted as traffic declined during the 20th century, and were re-laid for Jubilee line services that started in 1999. The current [[Docklands Light Railway]] (ex-North London line) uses the original eastern alignment and the Jubilee uses the western alignment.{{sfnp|Brown|2012}}
;Northern line
:The line from [[East Finchley tube station|East Finchley]] to [[Mill Hill East tube station|Mill Hill East]] was opened in 1867, and from [[Finchley Central tube station|Finchley Central]] to [[High Barnet tube station|High Barnet]] in 1872, both by the [[Great Northern Railway (Great Britain)|Great Northern Railway]].{{sfnp|Brown|2012}}
;Piccadilly line
:The westbound track between east of Ravenscourt Park and Turnham Green was built by LSWR in 1869, and originally used for eastbound main-line and District services. The eastbound track was built in 1911; it closed in 1916 but was re-used when the Piccadilly line was extended in 1932.{{sfnp|Brown|2012}}

===Main line services using LU tracks===
[[Chiltern Railways]] shares track with the Metropolitan Line between Harrow-on-the-Hill and Amersham.  Three [[South Western Railway (train operating company)|South Western Railway]] passenger trains a day use District Line tracks between Wimbledon and East Putney.<ref>{{cite web |last1=Maund |first1=Richard |title=Passenger Train Services over Unusual Lines |url=http://www.psul4all.free-online.co.uk/2021.html |access-date=22 October 2021 |quote="Point Pleasant Junction – East Putney" |archive-date=22 October 2021 |archive-url=https://web.archive.org/web/20211022142438/http://www.psul4all.free-online.co.uk/2021.html |url-status=dead }}</ref>

===Trains===
{{Main|London Underground rolling stock}}
[[File:London Underground subsurface and tube trains.jpg|thumb| A sub-surface [[Metropolitan line]] [[London Underground A60 and A62 Stock|A Stock]] train (left) passes a deep-tube [[Piccadilly line]] [[London Underground 1973 Stock|1973 Stock]] train (right) in the siding at [[Rayners Lane tube station|Rayners Lane]].]]
London Underground trains come in two sizes, larger sub-surface trains and smaller deep-tube trains.<ref>{{cite web |url=http://www.tfl.gov.uk/corporate/about-tfl/what-we-do/london-underground/rolling-stock |title=Rolling Stock |publisher=Transport for London |access-date=18 June 2014 |archive-date=19 May 2014 |archive-url=https://web.archive.org/web/20140519013214/http://www.tfl.gov.uk/corporate/about-tfl/what-we-do/london-underground/rolling-stock |url-status=live }}</ref> Since the early 1960s all passenger trains have been [[electric multiple unit]]s with sliding doors{{sfnp|Day|Reed|2010|p=159}} and a train last ran with a guard in 2000.{{sfnp|Day|Reed|2010|p=205}}  All lines use fixed-length trains with between six and eight cars, except for the Waterloo & City line that uses four cars.<ref name="RSData">{{cite web |archive-url=https://web.archive.org/web/20131004231025/http://www.tfl.gov.uk/assets/downloads/foi/Rolling_stock_Data_Sheet_2nd_Edition.pdf |title=Rolling Stock Data Sheet |publisher=Transport for London |date=March 2007 |archive-date=4 October 2013 |url=http://www.tfl.gov.uk/assets/downloads/foi/Rolling_stock_Data_Sheet_2nd_Edition.pdf |url-status=live }}</ref> New trains are designed for maximum number of [[standing passenger]]s and for speed of access to the cars and have [[regenerative braking]] and public address systems.<ref name="Connor">{{cite news |title=Deep tube transformation |last=Connor |first=Piers |work=[[Modern Railways]] |date=January 2013 |pages=44–47}}</ref> Since 1999 all new stock has had to comply with accessibility regulations that require such things as access and room for wheelchairs, and the size and location of door controls. All underground trains are required to comply with [[Rail Vehicle Accessibility Regulations|The Rail Vehicle Accessibility (Non Interoperable Rail System) Regulations 2010]] (RVAR 2010) by 2020.<ref name="gov">{{cite web |url=https://www.gov.uk/government/policies/making-transport-more-accessible-to-all/supporting-pages/accessible-transport-for-all |title=Making transport more accessible to all |publisher=[[Department for Transport]] |date=3 October 2012 |access-date=17 March 2013 |archive-date=17 September 2013 |archive-url=https://web.archive.org/web/20130917191505/https://www.gov.uk/government/policies/making-transport-more-accessible-to-all/supporting-pages/accessible-transport-for-all |url-status=live }}</ref>

Stock on sub-surface lines is identified by a letter (such as [[London Underground S7 and S8 Stock|S Stock]], used on the [[Metropolitan line]]), while tube stock is identified by the year of intended introduction{{sfnp|Hardy|2002|p=6}} (for example, [[London Underground 1996 Stock|1996 Stock]], used on the Jubilee line).

===Depots===
The Underground is served by the following depots:
* [[Bakerloo line|Bakerloo]]: [[Stonebridge Park Depot|Stonebridge Park]], Queen's Park, London Road
* [[Central line (London Underground)|Central]]: [[Hainault Depot|Hainault]], [[Ruislip Depot|Ruislip]], [[White City Depot|White City]]
* [[Circle line (London Underground)|Circle]]: [[Hammersmith Depot|Hammersmith]]
* [[District line|District]]: [[Ealing Common Depot|Ealing Common]], [[Lillie Bridge Depot|Lillie Bridge]], [[Upminster Depot|Upminster]]
* [[Hammersmith & City line|Hammersmith & City]]: [[Hammersmith Depot|Hammersmith]]
* [[Jubilee line|Jubilee]]: [[Neasden Depot|Neasden]], [[Stratford Market Depot|Stratford Market]]
* [[Metropolitan line|Metropolitan]]: [[Neasden Depot|Neasden]]
* [[Northern line|Northern]]: Edgware, Golders Green, Highgate, [[Morden Depot|Morden]]
* [[Piccadilly line|Piccadilly]]: Cockfosters, Northfields
* [[Victoria line|Victoria]]: [[Northumberland Park Depot|Northumberland Park]]
* [[Waterloo & City line|Waterloo & City]]: [[Waterloo Underground Depot|Waterloo]]
*London Underground: [[Acton Works]]

===Disused and abandoned stations===
{{main|List of former and unopened London Underground stations}}
In the years since the first parts of the London Underground opened, many stations and routes have been closed. Some stations were closed because of low passenger numbers rendering them uneconomical; some became redundant after lines were re-routed or replacements were constructed; and others are no longer served by the Underground but remain open to [[National Rail]] main line services. In some cases, such as [[Aldwych tube station|Aldwych]] and [[Ongar railway station|Ongar]], the buildings remain and are used for other purposes. In others, such as [[British Museum tube station|British Museum]], all evidence of the station has been lost through demolition.

[[London Transport Museum]] runs guided tours of several disused stations including [[Down Street tube station|Down Street]] and Aldwych through its "Hidden London" programme. The tours look at the history of the network and feature historical details drawn from the museum's own archives and collections.<ref>{{Cite web |title=New Tickets Released for Hidden London tours |url=https://www.ltmuseum.co.uk/news/new-tickets-released-hidden-london-tours |access-date=15 February 2023 |website=London Transport Museum |date=25 January 2023 |language=en |archive-date=5 November 2023 |archive-url=https://web.archive.org/web/20231105190956/https://www.ltmuseum.co.uk/news/new-tickets-released-hidden-london-tours |url-status=live }}</ref>

=== Proposed line extensions ===
[[File:London Underground proposed Bakerloo line extension map.svg|thumb|upright=1.35|Proposed route, [[Safeguarding (planning law)|safeguarded]] by TfL in 2021]]

====Bakerloo line extension to Lewisham====
{{main|Bakerloo line extension}}
A southern extension of the [[Bakerloo line]] from [[Elephant & Castle tube station|Elephant & Castle]] has been proposed multiple times since the line opened. In the 2010s, consultation events and preliminary design work took place on an extension. A route from [[Elephant & Castle tube station|Elephant & Castle]] to [[Lewisham station|Lewisham]] via the [[Old Kent Road]] and {{rws|New Cross Gate}} was chosen by Transport for London in 2019.<ref>{{Cite web |date=14 October 2019 |title=New consultation on Bakerloo line extension opens today |url=https://tfl.gov.uk/info-for/media/press-releases/2020/october/new-consultation-on-bakerloo-line-extension-opens-today |url-status=live |access-date=2 April 2021 |website=Transport for London |language=en-GB |archive-date=26 October 2022 |archive-url=https://web.archive.org/web/20221026072305/https://tfl.gov.uk/info-for/media/press-releases/2020/october/new-consultation-on-bakerloo-line-extension-opens-today }}</ref> The line could be extended further on the [[Hayes line|Hayes National Rail line]] in future. Estimated to cost between £4.7{{nbsp}}billion to £7.9{{nbsp}}billion (in 2017 prices), the extension would take around 7 years to construct.<ref name=":11">{{Cite web |date=October 2019 |title=Bakerloo line extension Background to Consultation Summary Report October 2019 |url=https://consultations.tfl.gov.uk/tube/bakerloo-extension/user_uploads/background-summary-report.pdf |url-status=live |archive-url=https://web.archive.org/web/20200324162143/https://consultations.tfl.gov.uk/tube/bakerloo-extension/user_uploads/background-summary-report.pdf |archive-date=24 March 2020 |access-date=15 March 2021 |publisher=Transport for London}}</ref> Due to financial impacts of the [[COVID-19 pandemic]], work to implement the extension is currently on hold.<ref name=":02">{{Cite web |title=Planning for the Future – Bakerloo line extension |url=https://www.tfl.gov.uk/corporate/about-tfl/how-we-work/planning-for-the-future/bakerloo-line-extension |url-status=live |archive-url=https://web.archive.org/web/20150929005921/https://tfl.gov.uk/corporate/about-tfl/how-we-work/planning-for-the-future/bakerloo-line-extension |archive-date=29 September 2015 |access-date=15 March 2021 |publisher=[[Transport for London]]}}</ref>

==== Other proposed extensions and lines ====
Several other extensions have been proposed in recent years, including a further [[Northern line extension to Battersea|extension of the Northern line]] to [[Clapham Junction railway station|Clapham Junction]].<ref>{{cite news |last=Henderson |first=Jamie |date=23 June 2013 |title=Clapham Junction next for Northern Line says London Assembly member |newspaper=Wandsworth Guardian |url=http://www.wandsworthguardian.co.uk/news/10501385.Clapham_Junction_next_for_Northern_Line_says_London_Assembly_member/ |access-date=12 January 2014 |archive-date=24 December 2013 |archive-url=https://web.archive.org/web/20131224115148/http://www.wandsworthguardian.co.uk/news/10501385.Clapham_Junction_next_for_Northern_Line_says_London_Assembly_member/ |url-status=live }}</ref> The long proposed [[Croxley Rail Link]] (an extension of the [[Metropolitan line]]) was cancelled in 2018 due to higher than expected costs and lack of funding.<ref>{{cite web |title=Metropolitan line extension |url=https://tfl.gov.uk/travel-information/improvements-and-projects/metropolitan-line-extension |url-status=dead |archive-url=https://web.archive.org/web/20170717143418/https://tfl.gov.uk/travel-information/improvements-and-projects/metropolitan-line-extension |archive-date=17 July 2017 |access-date=17 July 2017 |publisher=Transport for London}}</ref><ref>{{Cite web |last=Smith |first=Rebecca |date=8 February 2018 |title=Metropolitan Line extension stalemate between mayor Sadiq Khan and government leaves TFL mulling bus scheme alternative |url=http://www.cityam.com/266474/metropolitan-line-extension-stalemate-between-mayor-sadiq |access-date=26 October 2022 |website=City AM |archive-date=18 February 2019 |archive-url=https://web.archive.org/web/20190218081822/http://www.cityam.com/266474/metropolitan-line-extension-stalemate-between-mayor-sadiq |url-status=live }}</ref>

In 2019, the [[Canary Wharf Group]] suggested the construction of a new rail line between [[Euston tube station|Euston]] and [[Canary Wharf tube station|Canary Wharf]], to improve connections to the future [[High Speed 2]] railway.<ref>{{cite web |last=Smale |first=Katherine |url=https://www.newcivilengineer.com/latest/exclusive-canary-wharf-group-in-talks-about-rail-link-to-euston/10041923.article |title=Canary Wharf Group in talks about rail link to Euston |date=11 April 2019 |publisher=[[New Civil Engineer]] |access-date=25 April 2019 |archive-date=13 April 2019 |archive-url=https://web.archive.org/web/20190413152129/https://www.newcivilengineer.com/latest/exclusive-canary-wharf-group-in-talks-about-rail-link-to-euston/10041923.article |url-status=live }}</ref>

In 2021, [[Harlow District Council]] proposed extending the [[Central Line (London Underground)|Central line]] from its eastern terminus in [[Epping tube station|Epping]] to [[Harlow]]. They argued this would reduce travel times to Epping and London, and help with efforts to add 19,000 new homes to the town and expand the population to 130,000. However, no funding has been allocated for this proposed extension.<ref>{{Cite news |date=11 August 2021 |title=Harlow's addition to London Underground proposed by council |language=en-GB |work=BBC News |url=https://www.bbc.com/news/uk-england-essex-58172373 |access-date=26 March 2023 |archive-date=25 March 2023 |archive-url=https://web.archive.org/web/20230325231841/https://www.bbc.com/news/uk-england-essex-58172373 |url-status=live }}</ref>

===Line improvements===
{{more citations needed section|date=June 2015}}

====Bakerloo line====
The thirty-six 1972-stock trains on the Bakerloo line have already exceeded their original design life of 40 years. London Underground is therefore extending their operational life by making major repairs to many of the trains to maintain reliability. The Bakerloo line will receive new trains as part of the [[New Tube for London]] project. This will replace the existing fleet with new air-cooled [[articulated car|articulated trains]] and a new signalling system to allow [[Automatic Train Operation]]. The line is predicted to run a maximum of 27 trains per hour, a 25% increase on the current 21 trains per hour during peak periods.<ref name="New Tube for London Feasibility Report">{{cite web |title=New Tube for London Feasibility Report |url=https://tfl.gov.uk/cdn/static/cms/documents/ntfl-feasibility-report.pdf |publisher=TfL |date=October 2014 |access-date=25 June 2015 |archive-date=26 June 2015 |archive-url=https://web.archive.org/web/20150626151325/https://tfl.gov.uk/cdn/static/cms/documents/ntfl-feasibility-report.pdf |url-status=dead }}</ref><ref name="Bakerloo line 1972 stock train overhall">{{cite web |title=Bakerloo Line Fleet Life Extension |date=11 March 2015 |url=https://tfl.gov.uk/cdn/static/cms/documents/fpc-20150311-part-1-item15-bakerloo-line.pdf |publisher=TfL |access-date=25 June 2015 |archive-date=26 June 2015 |archive-url=https://web.archive.org/web/20150626133010/https://tfl.gov.uk/cdn/static/cms/documents/fpc-20150311-part-1-item15-bakerloo-line.pdf |url-status=live }}</ref>

====Central line====
[[File:The new Shepherd's Bush Underground station - geograph.org.uk - 2421843.jpg|thumb|The new [[Shepherd's Bush tube station|Shepherd's Bush]] station, part of a [[Central line (London Underground)|Central line]] improvement]]
The Central line was the first line to be modernised in the 1990s, with 85 new 1992-stock trains and a new automatic signalling system installed to allow Automatic Train Operation. The line runs 34 trains per hour for half an hour in the morning peak but is unable to operate more frequently because of a lack of additional trains. The 85 existing 1992-stock trains are the most unreliable on the London Underground as they are equipped with the first generation of solid-state direct-current thyristor-control traction equipment. The trains often break down, have to be withdrawn from service at short notice and at times are not available when required, leading to gaps in service at peak times. Although relatively modern and well within their design life, the trains need work in the medium term to ensure the continued reliability of the traction control equipment and maintain fleet serviceability until renewal, which is expected between 2028 and 2032. Major work is to be undertaken on the fleet to ensure their continued reliability with brakes, traction control systems, doors, automatic control systems being repaired or replaced, among other components. The Central line will be part of the New Tube for London Project. This will replace the existing fleet with new air-cooled walkthrough trains and a new automatic signalling system. The line is predicted to run 36 trains per hour, a 25% increase compared to the present service of 34 trains for the busiest 30 minutes in the morning and evening peaks and 27–30 trains per hour during the rest of the peak.<ref name="New Tube for London Feasibility Report" /><ref name="Report on Central Line train overhaul">{{cite web |title= Central line train overhaul project |url= https://tfl.gov.uk/cdn/static/cms/documents/fpc-20150311-part-1-item16-central-line-overhaul.pdf |publisher= TfL |access-date= 25 June 2015 |archive-date= 26 June 2015 |archive-url= https://web.archive.org/web/20150626134753/https://tfl.gov.uk/cdn/static/cms/documents/fpc-20150311-part-1-item16-central-line-overhaul.pdf |url-status= live }}</ref><ref>{{cite web |title=Central line timetable |url= https://tfl.gov.uk/cdn/static/cms/documents/wtt-67-central-15-september-2013.pdf |archive-url= https://web.archive.org/web/20140415231448/http://tfl.gov.uk/cdn/static/cms/documents/wtt-67-central-15-september-2013.pdf |url-status= dead |archive-date= 15 April 2014 |publisher=TfL |access-date=25 June 2015}}</ref>

====Jubilee line====
The signalling system on the Jubilee line has been replaced to increase capacity on the line by 20%—the line now runs 30 trains per hour at peak times, compared to the previous 24 trains per hour. As with the Victoria line, the service frequency is planned to increase to 36 trains per hour. To enable this, ventilation, power supply and control and signalling systems will be adapted and modified to allow the increase in frequency. London Underground also plans to add up to an additional 18 trains to the current fleet of 63 trains of 1996 stock.<ref>{{cite web |title=Jubilee line 36tph upgrade |url=https://tfl.gov.uk/cdn/static/cms/documents/fpc-20141014-part-1-item-18-jubilee-line-wcc.pdf |publisher=TfL |access-date=25 June 2015 |archive-date=20 April 2015 |archive-url=https://web.archive.org/web/20150420123135/http://www.tfl.gov.uk/cdn/static/cms/documents/fpc-20141014-part-1-item-18-jubilee-line-wcc.pdf |url-status=live }}</ref><ref name="PR20140818">{{cite press release |title=LU to source additional Tube trains |url=https://tfl.gov.uk/info-for/media/press-releases/2014/august/lu-to-source-additional-tube-trains |publisher=TfL |access-date=25 June 2015 |date=18 August 2014 |archive-date=26 June 2015 |archive-url=https://web.archive.org/web/20150626120519/https://tfl.gov.uk/info-for/media/press-releases/2014/august/lu-to-source-additional-tube-trains |url-status=live }}</ref>

====Northern line====
The signalling system on the Northern line has been replaced to increase capacity on the line by 20%, as the line now runs 24 trains per hour at peak times, compared to 20 previously. Capacity can be increased further if the operation of the Charing Cross and Bank branches is separated. To enable this up to 50 additional trains will be built in addition to the current 106 1995 stock. Five trains will be required for the Northern line extension and 45 to increase frequencies on the rest of the line. This, combined with segregation of trains at Camden Town junction, will allow 30–36 trains per hour compared to 24 trains per hour currently.<ref name="PR20140818" /><ref>{{cite web |title=Information on the Northern Line upgrade |url= http://www.railway-technical.com/Northern-Interview-article-for-MR-v5.pdf |publisher= railway-technical |access-date=25 June 2015 |url-status=dead |archive-url= https://web.archive.org/web/20150830075238/http://www.railway-technical.com/Northern-Interview-article-for-MR-v5.pdf |archive-date=30 August 2015 }}</ref>

====Piccadilly line====
The eighty-six 1973 stock trains that operate on the Piccadilly line are some of the most reliable trains on the London Underground. The trains have exceeded their design life of around 40 years and are in need of replacement. The Piccadilly line will be part of the New Tube for London Project. This will replace the existing fleet with new air-cooled walk-through trains and a new signalling system to allow Automatic Train Operation. The line is predicted to run 30–36 trains per hour, up to a 50% increase compared to the 24–25 train per hour service provided today. The line will be the first to be upgraded as part of the New Tube for London Project, as passenger numbers have increased over recent years and are expected to increase further. This line is important in this project because it currently provides a less frequent service than other lines.<ref name="New Tube for London Feasibility Report"/>

====Victoria line====
The signalling system on the Victoria line has been replaced to increase capacity on the line by around 25%; the line now runs up to 36 trains per hour compared to 27–28 previously. The trains have been replaced with 47 new higher-capacity 2009-stock trains. The peak frequency was increased to 36 trains per hour in 2016 after track works were completed to the layout of the points at Walthamstow Central crossover, which transfers northbound trains to the southbound line for their return journey. This resulted in a 40% increase in capacity between Seven Sisters and Walthamstow Central.<ref>{{cite press release |title=Major works to improve Victoria line services this summer |url=https://tfl.gov.uk/info-for/media/press-releases/2015/february/major-works-to-improve-the-victoria-line-over-the-summ |publisher=TfL |date=17 February 2015 |access-date=25 June 2015 |archive-date=24 May 2015 |archive-url=https://web.archive.org/web/20150524035913/http://www.tfl.gov.uk/info-for/media/press-releases/2015/february/major-works-to-improve-the-victoria-line-over-the-summ |url-status=live }}</ref><ref>{{Cite news |url=https://www.guardian-series.co.uk/news/14492247.victoria-line-trains-run-end-end-first-time/ |title=All Victoria Line trains to run 'end to end' for first time |work=East London and West Essex Guardian Series |location=Watford |date=13 May 2016 |first=Tom |last=Barnes |access-date=21 April 2021 |archive-date=10 May 2021 |archive-url=https://web.archive.org/web/20210510042703/https://www.guardian-series.co.uk/news/14492247.victoria-line-trains-run-end-end-first-time/ |url-status=live }}</ref>

====Waterloo & City line====
The line was upgraded with five new 1992-stock trains in the early 1990s, at the same time as the Central line was upgraded. The line operates under traditional signalling and does not use Automatic Train Operation. The line will be part of the New Tube for London Project. This will replace the existing fleet with new air-cooled walk-through trains and a new signalling system to allow Automatic Train Operation. The line is predicted to run 30 trains per hour, an increase of up to 50% on the current 21 trains per hour. The line may also be one of the first to be upgraded, alongside the Piccadilly line, with new trains, systems and platform-edge doors to test the systems before the Central and Bakerloo lines are upgraded.<ref name="New Tube for London Feasibility Report"/>

====Sub-surface lines (District, Metropolitan, Hammersmith & City and Circle)====
{{main|Four Lines Modernisation}}

New S Stock trains have been introduced on the sub-surface (District, Metropolitan, Hammersmith & City and Circle) lines. These were all delivered by 2017. 191 trains have been introduced: 58 for the Metropolitan line and 133 for the Circle, District and Hammersmith & City lines. The track, electrical supply and signalling systems are also being upgraded in a programme to increase peak-hour capacity. The replacement of the signalling system and the introduction of Automatic Train Operation and Control is scheduled for 2019–22. A control room for the sub-surface network has been built in Hammersmith and an automatic train control (ATC) system is to replace ageing signalling equipment dating from between the mid-1920s and late 1980s, including the signal cabin at Edgware Road, the control room at Earl's Court, and the signalling centre at Baker Street. Bombardier won the contract in June 2011 but was released by agreement in December 2013, and London Underground has now issued another signalling contract, with Thales.<ref>{{cite web |title=Tube Improvements |url= https://tfl.gov.uk/campaign/tube-improvements/what-we-ve-done |date=n.d. |publisher=TfL |access-date=25 June 2015 |archive-url= https://web.archive.org/web/20150711143215/https://tfl.gov.uk/campaign/tube-improvements/what-we-ve-done |archive-date=11 July 2015 |url-status=dead }}</ref><ref>{{cite web |title= Third Time Lucky: A Look At The New Sub-Surface Signalling Plan |url= http://www.londonreconnections.com/2015/subsurface-railway-resignalling-saga-continues/ |date= 15 June 2015 |website= London Reconnections |access-date= 25 June 2015 |archive-date= 26 June 2015 |archive-url= https://web.archive.org/web/20150626103653/http://www.londonreconnections.com/2015/subsurface-railway-resignalling-saga-continues/ |url-status= live }}</ref><ref>{{cite web |title=SSR Signalling contract |url=https://tfl.gov.uk/cdn/static/cms/documents/fpc-20150617-item17-part-1-four-lines-modernisation.pdf |publisher=TfL |access-date=25 June 2015 |archive-date=26 June 2015 |archive-url=https://web.archive.org/web/20150626145855/https://tfl.gov.uk/cdn/static/cms/documents/fpc-20150617-item17-part-1-four-lines-modernisation.pdf |url-status=live }}</ref>

===New trains for deep-level lines===
{{main|New Tube for London}}{{Update section|date=June 2024}}
In mid-2014, Transport for London issued a tender for up to 18 trains for the Jubilee line and up to 50 trains for the Northern line. These would be used to increase frequencies and cover the Battersea extension on the Northern line.<ref>{{Cite web|url=http://www.railtechnologymagazine.com/Rail-News/lu-begins-search-for-new-jubilee-and-northern-line-train-supplier|archive-url=https://web.archive.org/web/20200803140346/http://www.railtechnologymagazine.com/Rail-News/lu-begins-search-for-new-jubilee-and-northern-line-train-supplier|url-status=dead|archive-date=3 August 2020|title=LU begins search for new Jubilee and Northern line train supplier|website=www.railtechnologymagazine.com|access-date=5 October 2019}}</ref>

In early 2014, the Bakerloo, Central, Piccadilly and Waterloo & City line rolling-stock replacement project was renamed ''New Tube for London'' (NTfL) and moved from the feasibility stage to the design and specification stage. The study had shown that, with new generation trains and re-signalling:
* Piccadilly line capacity could be increased by 60% with 33 trains per hour (tph) at peak times by 2025.
* Central line capacity increased by 25% with 33 tph at peak times by 2030.
* Waterloo & City line capacity increased by 50% by 2032, after the track at Waterloo station is remodelled.
* Bakerloo line capacity could be increased by 25% with 27 tph at peak times by 2033.
The project is estimated to cost £16.42{{nbsp}}billion (£9.86{{nbsp}}billion at 2013 prices). A notice was published on 28 February 2014 in the [[Official Journal of the European Union]] asking for expressions of interest in building the trains.<ref name="tfl20140205part1item10">{{cite web |url=http://www.tfl.gov.uk/cdn/static/cms/documents/board-20140205-part-1-item10-new-tube-for-london.pdf |title=New Tube for London Programme |publisher=Transport for London |work=Board Minutes |date=5 February 2014 |access-date=3 April 2014 |archive-date=7 April 2014 |archive-url=https://web.archive.org/web/20140407072018/http://www.tfl.gov.uk/cdn/static/cms/documents/board-20140205-part-1-item10-new-tube-for-london.pdf |url-status=live }}</ref><ref name="rgazette20140228">{{cite news |url=http://www.railwaygazette.com/news/urban/single-view/view/london-underground-starts-new-tube-for-london-train-procurement.html |title=New Tube for London Programme |work=Railway Gazette |date=28 February 2014 |access-date=3 April 2014 |archive-date=10 March 2014 |archive-url=https://web.archive.org/web/20140310012844/http://www.railwaygazette.com/news/urban/single-view/view/london-underground-starts-new-tube-for-london-train-procurement.html |url-status=live }}</ref> On 9 October 2014, TFL published a shortlist of those ([[Alstom]], [[Siemens]], [[Hitachi]], [[Construcciones y Auxiliar de Ferrocarriles|CAF]] and [[Bombardier Transportation|Bombardier]]) who had expressed an interest in supplying 250 trains for between £1.0billion and £2.5billion, and on the same day opened an exhibition with a design by PriestmanGoode.<ref>{{cite press release |url=http://www.tfl.gov.uk/info-for/media/press-releases/2014/october/design-for-the-new-tube-for-london-revealed |title=Design for the 'New Tube for London' revealed |publisher=TfL |date=9 October 2014 |access-date=9 October 2014 |archive-date=15 May 2021 |archive-url=https://web.archive.org/web/20210515015540/https://tfl.gov.uk/info-for/media/press-releases/2014/october/design-for-the-new-tube-for-london-revealed |url-status=live }}</ref><ref name="bbc29520761">{{cite news |url=https://www.bbc.co.uk/news/uk-england-london-29520761 |title=New Tube for London Programme |work=BBC News |date=9 October 2014 |access-date=9 October 2014 |archive-date=20 June 2021 |archive-url=https://web.archive.org/web/20210620102851/https://www.bbc.co.uk/news/uk-england-london-29520761 |url-status=live }}</ref> The fully automated trains may be able to run without drivers,<ref name="Railnews">{{cite news |url=http://www.railnews.co.uk/news/2014/02/28-tfl-prepares-for-driverless-tube.html |title=TfL prepares for driverless tube |work=Railnews |date=28 February 2014 |access-date=3 April 2014 |archive-date=6 April 2014 |archive-url=https://web.archive.org/web/20140406181728/http://railnews.co.uk/news/2014/02/28-tfl-prepares-for-driverless-tube.html |url-status=live }}</ref> but the ASLEF and RMT trade unions that represent the drivers strongly oppose this, saying it would affect safety.<ref>{{cite news |url=https://www.bbc.co.uk/news/uk-england-london-26381175 |title=Driverless Tube trains: Unions vow 'war' over plan |work=BBC News |date=28 February 2014 |access-date=3 April 2014 |archive-date=30 April 2014 |archive-url=https://web.archive.org/web/20140430092816/http://www.bbc.co.uk/news/uk-england-london-26381175 |url-status=live }}</ref> The [[invitation to tender]] for the trains was issued in January 2016;<ref>{{cite news |title=New Tube for London invitations to tender issued |url=http://www.railwaygazette.com/news/single-view/view/new-tube-for-london-invitations-to-tender-issued.html |access-date=14 November 2016 |work=Railway Gazette |date=18 January 2016 |archive-date=4 July 2018 |archive-url=https://web.archive.org/web/20180704054555/http://www.railwaygazette.com/news/single-view/view/new-tube-for-london-invitations-to-tender-issued.html |url-status=live }}</ref> the specifications for the Piccadilly line infrastructure are expected in 2016,<ref name="tfl20140205part1item10" /><ref name="rgazette20140228" /> and the first train is due to run on the Piccadilly line in 2023.<ref>{{cite news|title=Khan: New Piccadilly rolling stock will be delivered by 2023|url=http://www.railtechnologymagazine.com/Rail-News/khan-new-piccadilly-rolling-stock-will-be-delivered-by-2023-|access-date=18 January 2018|work=Rail Technology Magazine|date=20 December 2016|archive-date=15 May 2021|archive-url=https://web.archive.org/web/20210515085329/https://www.railtechnologymagazine.com/Rail-News/khan-new-piccadilly-rolling-stock-will-be-delivered-by-2023-|url-status=live}}</ref> [[Siemens Mobility]]'s Inspiro design was selected in June 2018 in a £1.5billion contract.<ref>{{cite news |title=East Yorkshire factory wins £1.5bn Tube train deal |url=https://www.bbc.co.uk/news/uk-england-humber-44496526 |access-date=15 June 2018 |work=BBC News |date=15 June 2018 |archive-date=10 May 2021 |archive-url=https://web.archive.org/web/20210510124359/https://www.bbc.co.uk/news/uk-england-humber-44496526 |url-status=live }}</ref>

===Ventilation and cooling===
{{see also|London Underground infrastructure#Ventilation and cooling|label 1=London Underground infrastructure: Ventilation and cooling|London Underground cooling}}
When the Bakerloo line opened in 1906, it was advertised with a maximum temperature of {{convert|60|F}}, but over time the tube tunnels have warmed up.{{sfnp|Croome|Jackson|1993|pp=253–254}} In 1938 approval was given for a ventilation improvement programme, and a refrigeration unit was installed in a lift shaft at Tottenham Court Road.{{sfnp|Croome|Jackson|1993|pp=253–254}} Temperatures of {{convert|117|F}} were reported in the [[2006 European heat wave]].<ref>{{Cite news |url=http://news.bbc.co.uk/1/hi/england/london/5191604.stm |title=Baking hot at Baker Street |work=BBC News |date=18 July 2006 |access-date=31 March 2013 |last=Griffiths |first=Emma |archive-date=1 January 2016 |archive-url=https://web.archive.org/web/20160101055245/http://news.bbc.co.uk/1/hi/england/london/5191604.stm |url-status=live }}</ref> It was claimed in 2002 that, if animals were being transported, temperatures on the Tube would break European Commission animal welfare laws.<ref>{{cite news |url=https://www.telegraph.co.uk/news/1405628/Londons-Tube-unfit-for-animals.html |archive-url=https://ghostarchive.org/archive/20220111/https://www.telegraph.co.uk/news/1405628/Londons-Tube-unfit-for-animals.html |archive-date=11 January 2022 |url-access=subscription |url-status=live |title=London's Tube 'unfit for animals' |work=The Daily Telegraph |location=London |date=28 August 2002 |access-date=31 March 2013}}{{cbignore}}</ref> A 2000 study reported that air quality was 73 times worse than at street level, with a passenger inhaling the same mass of particulates during a twenty-minute journey on the Northern line as when smoking a cigarette.<ref>{{cite web |url=http://128.40.58.147/web/ben/Tube.htm |title=Environmental Quality in Underground Railways |publisher=University College London |date=4 December 2003 |access-date=5 November 2013 |author=Croxford, Ben |url-status=dead |archive-url=https://archive.today/20131016210006/http://128.40.58.147/web/ben/Tube.htm |archive-date=16 October 2013 }}</ref><ref>{{cite news |url=https://www.standard.co.uk/news/passengers-choke-on-the-tube-6304049.html |title=Passengers choke on the Tube |work=London Evening Standard |author=Murray, Dick |date=23 August 2002 |access-date=31 March 2013 |archive-date=8 November 2020 |archive-url=https://web.archive.org/web/20201108125625/https://www.standard.co.uk/news/passengers-choke-on-the-tube-6304049.html |url-status=live }}</ref> The main purpose of the London Underground's ventilation fans is to extract hot air from the tunnels,{{sfnp|Croome|Jackson|1993|pp=253–254}} and fans across the network are being refurbished, although complaints of noise from local residents preclude their use at full power at night.<ref>{{cite web |url=http://lurs.org.uk/documents/pdf%2008/jan/jan%20MEETING%20REPORT.pdf |title=Meeting Report: Cooling the tube |date=8 May 2007 |author1=Westgate, Stuart |author2=Gilby, Mark |publisher=LURS |access-date=31 March 2013 |archive-date=5 October 2013 |archive-url=https://web.archive.org/web/20131005010257/http://lurs.org.uk/documents/pdf%2008/jan/jan%20MEETING%20REPORT.pdf |url-status=live }}</ref>

In June 2006 a groundwater cooling system was installed at [[Victoria station (London)|Victoria station]].<ref>{{cite news |url=http://news.bbc.co.uk/1/hi/england/london/5058362.stm |title=Water pump plan to cool the Tube |work=BBC News |date=8 June 2006 |access-date=31 March 2013 |archive-date=6 July 2006 |archive-url=https://web.archive.org/web/20060706000031/http://news.bbc.co.uk/1/hi/england/london/5058362.stm |url-status=live }}</ref> In 2012, air-cooling units were installed on platforms at Green Park station using cool deep groundwater and at Oxford Circus using chiller units at the top of an adjacent building.<ref>{{cite press release |url=http://origin.tfl.gov.uk/corporate/media/newscentre/archive/22885.aspx |archive-url=https://archive.today/20140327171415/http://origin.tfl.gov.uk/corporate/media/newscentre/archive/22885.aspx |url-status=dead |archive-date=27 March 2014 |title=Work begins to cool the platforms at two major central London stations |publisher=Transport for London |date=17 February 2012 |access-date=27 March 2014 }}</ref> New air-conditioned trains have been introduced on the sub-surface lines, but were initially ruled out for the tube trains due to space being considered limited on tube trains for air-conditioning units and that these would heat the tunnels even more. The [[New Tube for London]], which will replace the trains for the Bakerloo, Central, Waterloo and City and Piccadilly lines, is planned to have air conditioning for the new trains along with better energy conservation and regenerative braking.<ref name="Connor" /><ref name="MR">{{cite news |work=Modern Railways |date=January 2013 |pages=38–41 |title=Sub-surface renewal |last=Abbott |first=James}}</ref><ref>{{Cite web|title=Improving the Tube – What we're doing – Improving the trains|url=https://www.tfl.gov.uk/campaign/tube-improvements/what-we-are-doing/improving-the-trains|access-date=21 August 2021|website=[[Transport for London]]|language=en-GB|archive-date=15 August 2021|archive-url=https://web.archive.org/web/20210815084031/https://tfl.gov.uk/campaign/tube-improvements/what-we-are-doing/improving-the-trains|url-status=live}}</ref>

In the original Tube design, trains passing through close fitting tunnels act as pistons to create air pressure gradients between stations. This pressure difference drives ventilation between platforms and the surface exits through the passenger foot network. This system depends on adequate cross-sectional area of the airspace above the passengers' heads in the foot tunnels and escalators, where laminar airflow is proportional to the fourth power of the radius, the [[Hagen–Poiseuille equation]]. It also depends on an absence of turbulence in the tunnel headspace. In many stations the ventilation system is now ineffective because of alterations that reduce tunnel diameters and increase turbulence. An example is Green Park tube station, where false ceiling panels attached to metal frames have been installed that reduce the above-head airspace diameter by more than half in many parts. This has the effect of reducing laminar airflow by 94%.

Originally, air turbulence was kept to a minimum by keeping all signage flat to the tunnel walls. Now, the ventilation space above head height is crowded with ducting, conduits, cameras, speakers and equipment acting as a baffle plates with predictable reductions in flow.<ref>{{Cite journal |last1=Demartini |first1=L. C. |last2=Vielmo |first2=H. A. |last3=Möller |first3=S. V. |title=Numeric and experimental analysis of the turbulent flow through a channel with baffle plates |journal=Journal of the Brazilian Society of Mechanical Sciences and Engineering |volume=26 |issue=2 |pages=153–159 |doi=10.1590/S1678-58782004000200006 |year=2004 |doi-access=free |hdl=10183/75781 |hdl-access=free | issn=1678-5878}}</ref> Often, electronic signs have their flat surface at right angles to the main air flow, causing choked flow. Temporary sign boards that stand at the top of escalators also maximise turbulence. The alterations to the ventilation system are important, not only to heat exchange.

==== Air quality ====
The [[Committee on the Medical Effects of Air Pollutants]] (COMEAP) has reported on the relative risks of breathing air pollution in different situations. In January 2019, for example, it reported that pollution from [[particulates]] is up to 30 times higher on the London Underground than on streets in the roads above, with the [[Northern Line]] having the worst air quality.<ref>{{cite news |last1=Finnis |first1=Alex |title=One hour on the tube is as toxic as standing next to a busy road for an entire day |url=https://inews.co.uk/news/uk/air-pollution-london-underground-tube-equivalent-busy-road-244546 |work=iNews |date=10 January 2019}}</ref><ref>{{cite news |last1=Oglesby |first1=Kate |title=Dust and air pollution higher on Northern Line than any other part of the Underground |work=The Times |date=12 January 2019}}</ref>{{needs update|date=October 2024}}

===Lifts and escalators===
{{see also|London Underground infrastructure#Lifts and escalators|label 1=London Underground infrastructure: Lifts and escalators|Accessibility of transport in London}}
[[File:Canary Wharf tube station night 2.jpg|thumb|left|Escalators at Canary Wharf station]]
Originally access to the deep-tube platforms was by a lift.{{sfnp|Croome|Jackson|1993|pp=26, 35, 39, 87–89}} Each lift was staffed, and at some quiet stations in the 1920s the ticket office was moved into the lift, or it was arranged that the lift could be controlled from the ticket office.{{sfnp|Croome|Jackson|1993|p=540}} The first escalator on the London Underground was installed in 1911 between the District and Piccadilly platforms at Earl's Court and from the following year new deep-level stations were provided with escalators instead of lifts.{{sfnp|Croome|Jackson|1993|pp=114, 542}} The escalators had a diagonal shunt at the top landing.{{sfnp|Croome|Jackson|1993|pp=114, 542}}{{sfnp|Day|Reed|2010|p=59}} In 1921 a recorded voice instructed passengers to stand on the right and signs followed in the Second World War.{{sfnp|Croome|Jackson|1993|pp=154, 546}} Travellers were asked to stand on the right so that anyone wishing to overtake them would have a clear passage on the left side of the escalator.<ref>{{Cite news |url=http://entertainment.timesonline.co.uk/tol/arts_and_entertainment/film/london_film_festival/article6883065.ece |title=Mystery over Tube escalator etiquette cleared up by restored film |last=Malvern |first=Jack |date=21 October 2009 |work=The Times |location=London |access-date=9 December 2009 |archive-date=15 June 2011 |archive-url=https://web.archive.org/web/20110615070709/http://entertainment.timesonline.co.uk/tol/arts_and_entertainment/film/london_film_festival/article6883065.ece |url-status=dead }}{{Subscription required}}</ref> The first 'comb' type escalator was installed in 1924 at [[Clapham Common tube station|Clapham Common]].{{sfnp|Croome|Jackson|1993|pp=114, 542}} In the 1920s and 1930s many lifts were replaced by escalators.{{sfnp|Day|Reed|2010|p=93}} After the fatal 1987 [[King's Cross fire]], all wooden escalators were replaced with metal ones and the mechanisms are regularly degreased to lower the potential for fires.<ref>{{cite web |url=https://www.pbs.org/wgbh/nova/escape/pioneers.html |title=Pioneers of Survival: Fire |publisher=PBS |access-date=4 September 2017 |archive-date=9 June 2021 |archive-url=https://web.archive.org/web/20210609050812/https://www.pbs.org/wgbh/nova/escape/pioneers.html |url-status=live }}</ref> The only wooden escalator not to be replaced was at [[Greenford station]], which remained until March 2014 when TfL replaced it with the first [[Incline elevator|incline lift]] on the UK transport network in October 2015.<ref>{{cite web |url=https://tfl.gov.uk/info-for/media/press-releases/2015/october/uk-first-as-incline-lift-opens-at-greenford-tube-station |archive-url=https://web.archive.org/web/20160629225202/https://tfl.gov.uk/info-for/media/press-releases/2015/october/uk-first-as-incline-lift-opens-at-greenford-tube-station |url-status=dead |archive-date=29 June 2016 |title=Incline lift at Greenford Tube station is UK first |publisher=Transport for London |date=20 October 2015 |access-date=21 October 2015 }}</ref>

There are 426 escalators on the London Underground system and the longest, at {{convert|60|m}}, is at [[Angel tube station|Angel]]. The shortest, at Stratford, gives a vertical rise of {{convert|4.1|m}}. There are 184 lifts,<ref>{{Cite web |url=https://tfl.gov.uk/corporate/about-tfl/what-we-do/london-underground/facts-and-figures |title=Facts & figures |website=[[Transport for London]] |access-date=20 November 2017 |archive-date=17 February 2017 |archive-url=https://web.archive.org/web/20170217173345/https://tfl.gov.uk/corporate/about-tfl/what-we-do/london-underground/facts-and-figures |url-status=live }}</ref> and numbers have increased in recent years because of investment in making tube stations accessible. Over 28 stations will have lifts installed over the next 10 years, bringing the total of step-free stations to over 100.<ref name="Matters">{{Cite web |title=Improvements and Projects – Step-free access |url=https://tfl.gov.uk/travel-information/improvements-and-projects/step-free-access?intcmp=1954 |access-date=19 November 2017 |publisher=Transport for London |archive-date=10 May 2021 |archive-url=https://web.archive.org/web/20210510075408/https://tfl.gov.uk/travel-information/improvements-and-projects/step-free-access?intcmp=1954 |url-status=live }}</ref> Lift and escalators are abundant with advertising posters which can be used for artistic purposes due to the nature of their layout.<ref>{{Cite web |date=31 December 2022 |title=London Underground Advertising {{!}} All Products & Formats |url= https://tubeadverts.co.uk/formats/ |access-date=8 January 2023}}</ref>
{{Clear}}

===Wi-Fi and mobile phone reception===
In mid-2012, London Underground, in partnership with [[Virgin Media]], trialled [[Wi-Fi]] hotspots in many stations, but not in the tunnels, that allowed passengers free internet access. The free trial proved successful and was extended to the end of 2012,<ref>{{cite news |work=Metro |location=London |url=http://www.metro.co.uk/tech/915263-virgin-media-extends-free-wi-fi-on-london-underground-until-2013 |title=Virgin Media extends free wi-fi on London Underground until 2013 |date=17 October 2012 |access-date=10 November 2012 |archive-date=20 November 2012 |archive-url=https://web.archive.org/web/20121120112803/http://www.metro.co.uk/tech/915263-virgin-media-extends-free-wi-fi-on-london-underground-until-2013 |url-status=dead }}</ref> whereupon it switched to a service freely available to subscribers to Virgin Media and others, or as a paid-for service.<ref>{{cite web |url=http://www.tfl.gov.uk/corporate/projectsandschemes/23939.aspx |title=Station Wifi |publisher=Transport for London |access-date=12 March 2013 |url-status=dead |archive-url=https://web.archive.org/web/20130225061959/http://www.tfl.gov.uk/corporate/projectsandschemes/23939.aspx |archive-date=25 February 2013}}</ref> It was not previously possible to use mobile phones on most parts of the Underground (excluding services running overground or occasionally sub-surface, depending on the phone and carrier) using native [[2G]], [[3G]] or [[4G]] networks, and a project to extend coverage before the [[2012 Olympics]] was abandoned because of commercial and technical difficulties.<ref>{{cite news |url=https://www.theguardian.com/politics/2011/apr/01/mobile-network-london-underground-shelved |title=Plans for mobile network on London underground shelved |newspaper=The Guardian |date=1 April 2011 |access-date=1 April 2013 |author=Mulholland, Hélène |location=London |archive-date=23 May 2021 |archive-url=https://web.archive.org/web/20210523143145/https://www.theguardian.com/politics/2011/apr/01/mobile-network-london-underground-shelved |url-status=live }}</ref>

In March 2020, [[2G]], [[3G]] and [[4G]] signal was made available on parts of the Jubilee line, between Westminster and Canning Town, throughout the stations and tunnels as part of an initial trial.<ref>{{Cite press release|url=https://tfl.gov.uk/info-for/media/press-releases/2019/july/4g-on-jubilee-line-tunnel-section-from-march-2020|title=4G on Jubilee line tunnel section from March 2020|website=Transport for London|access-date=3 August 2020|archive-date=10 May 2021|archive-url=https://web.archive.org/web/20210510121751/https://tfl.gov.uk/info-for/media/press-releases/2019/july/4g-on-jubilee-line-tunnel-section-from-march-2020|url-status=live}}</ref>

In June 2021, Vodafone dropped London Underground Wi-Fi connectivity across the entire network.<ref>{{Cite web |last=Jackson |first=Mark |date=17 June 2021 |title=Vodafone UK Quietly Scrap London Underground WiFi Support |url=https://www.ispreview.co.uk/index.php/2021/06/vodafone-uk-quietly-scrap-london-underground-wifi-support.html |access-date=19 August 2023 |website=ISPreview UK |language=en |archive-date=19 August 2023 |archive-url=https://web.archive.org/web/20230819234719/https://www.ispreview.co.uk/index.php/2021/06/vodafone-uk-quietly-scrap-london-underground-wifi-support.html |url-status=live }}</ref><ref>{{cite web |last=Mansfield |first=Ian |date=17 June 2021 |title=Vodafone drops WiFi coverage from the London Underground |url=https://www.ianvisits.co.uk/articles/vodafone-drops-wi-fi-coverage-from-the-london-underground-44397/ |access-date=19 August 2023 |website=ianVisits |language=en-GB |archive-date=19 August 2023 |archive-url=https://web.archive.org/web/20230819234718/https://www.ianvisits.co.uk/articles/vodafone-drops-wi-fi-coverage-from-the-london-underground-44397/ |url-status=live }}</ref> This was restored in April 2023 after control of the Wi-Fi connectivity moved from Virgin Media to [[BAI Communications|Boldyn Networks]] as part of their 20-year concession deal with Transport for London, providing data connectivity across the entire network.<ref>{{Cite web |last=Jackson |first=Mark |date=3 April 2023 |title=Vodafone UK Reintroduced Public WiFi to London Underground |url=https://www.ispreview.co.uk/index.php/2023/04/vodafone-uk-reintroduced-public-wifi-to-london-underground.html |access-date=19 August 2023 |website=ISPreview UK |language=en |archive-date=19 August 2023 |archive-url=https://web.archive.org/web/20230819234717/https://www.ispreview.co.uk/index.php/2023/04/vodafone-uk-reintroduced-public-wifi-to-london-underground.html |url-status=live }}</ref>

In December 2022, additional mobile coverage, including [[5G]] connectivity, launched at a small subset of stations and tunnel segments on the [[Central line (London Underground)|Central line]], with a view to expand to the full set of sub-surface stations and tunnels on the London Underground, and also the [[Elizabeth line|Elizabeth Line]], by the end of 2024.<ref>{{Cite web |last=Transport for London |date=21 December 2022 |title=Three more London Underground stations begin offering high-speed mobile coverage to customers |url=https://tfl.gov.uk/info-for/media/press-releases/2022/december/three-more-london-underground-stations-begin-offering-high-speed-mobile-coverage-to-customers |access-date=19 August 2023 |website=Transport for London |language=en-GB |archive-date=19 August 2023 |archive-url=https://web.archive.org/web/20230819234717/https://tfl.gov.uk/info-for/media/press-releases/2022/december/three-more-london-underground-stations-begin-offering-high-speed-mobile-coverage-to-customers |url-status=live }}</ref><ref>{{Cite web |last=Jackson |first=Mark |date=21 December 2022 |title=EE and Vodafone UK Extend 4G Mobile to 6 New London Underground Stations |url=https://www.ispreview.co.uk/index.php/2022/12/ee-uk-extend-4g-mobile-to-six-new-london-underground-stations.html |access-date=19 August 2023 |website=ISPreview UK |language=en |archive-date=19 August 2023 |archive-url=https://web.archive.org/web/20230819234718/https://www.ispreview.co.uk/index.php/2022/12/ee-uk-extend-4g-mobile-to-six-new-london-underground-stations.html |url-status=live }}</ref> Further stations on the Northern line were launched from January 2023, with additional Northern line stations also being added in June 2023. Not all stations have identical coverage solutions, with some not having 5G connectivity present.<ref name=":9">{{Cite web |title=London Underground mobile connectivity map |url=https://mastdatabase.co.uk/gb/london-underground-connectivity/ |access-date=19 August 2023 |website=mastdatabase.co.uk |language=en-GB |archive-date=19 August 2023 |archive-url=https://web.archive.org/web/20230819234718/https://mastdatabase.co.uk/gb/london-underground-connectivity/ |url-status=live }}</ref> As of June 2023, testing has begun on sections of the Bakerloo, Piccadilly and Victoria lines.<ref name=":10">{{cite web |last=Mansfield |first=Ian |date=20 June 2023 |title=London Underground expands mobile phone coverage to Mornington Crescent station |url=https://www.ianvisits.co.uk/articles/london-underground-expands-mobile-phone-coverage-to-mornington-crescent-station-63634/ |access-date=19 August 2023 |website=ianVisits |language=en-GB |archive-date=19 August 2023 |archive-url=https://web.archive.org/web/20230819234717/https://www.ianvisits.co.uk/articles/london-underground-expands-mobile-phone-coverage-to-mornington-crescent-station-63634/ |url-status=live }}</ref><ref name=":12">{{cite web |last=Mansfield |first=Ian |date=8 September 2023 |title=London Underground expands mobile phone coverage and confirms Elizabeth line coming soon |url=https://www.ianvisits.co.uk/articles/london-underground-expands-mobile-phone-coverage-and-confirms-elizabeth-line-coming-soon-65587/ |access-date=15 December 2023 |website=ianVisits |language=en-GB |archive-date=15 December 2023 |archive-url=https://web.archive.org/web/20231215232412/https://www.ianvisits.co.uk/articles/london-underground-expands-mobile-phone-coverage-and-confirms-elizabeth-line-coming-soon-65587/ |url-status=live }}</ref>

In November and December 2023, more mobile data coverage was launched on more stations on the Northern and Central Lines. On the Northern line: all stations from Tottenham Court Road to Euston. on the Central line: from Oxford Circus to Chancery Lane.<ref>{{cite web |title=Mobile phones and Wi-Fi underground |url=https://tfl.gov.uk/campaign/station-wifi |website=Transport for London |access-date=9 January 2024 |archive-date=9 January 2024 |archive-url=https://web.archive.org/web/20240109131330/https://tfl.gov.uk/campaign/station-wifi |url-status=live }}</ref>

{| class="wikitable sortable"
|+Mobile coverage availability on London Underground<ref name=":9" /><ref name=":13">{{Cite web |date=February 2024 |title=Tube Map 4g - 5g Feb 2024 |url=https://content.tfl.gov.uk/below-ground-4g-5g-tube-map-february-2024.pdf |website=Transport for london |access-date=12 March 2024 |archive-date=12 March 2024 |archive-url=https://web.archive.org/web/20240312095020/https://content.tfl.gov.uk/below-ground-4g-5g-tube-map-february-2024.pdf |url-status=dead }}</ref>
!Line
!Sections of track or stations
!Available from
|-
|[[Jubilee line|Jubilee]]
|Westminster – Canning Town
|March 2020
|-
|[[Central line (London Underground)|Central]]
|Holland Park – Queensway
|December 2022
|-
|[[Central line (London Underground)|Central]]
|Oxford Circus – Tottenham Court Road
|September 2023
|-
|[[Northern line|Northern]]
|Archway – Kentish Town
|January 2023
|-
|[[Northern line|Northern]]
|Tottenham Court Road
|December 2023
|-
|[[Northern line|Northern]]
|Camden Town
|December 2023
|-
|[[Northern line|Northern]]
|Kentish Town – Mornington Crescent
|July 2023
|-
|[[Northern line|Northern]]
|Archway – East Finchley
|January 2024 – Highgate platforms have service, not the tunnels. Expected from Spring 2024<ref name=":12" />
|-
|[[Piccadilly line (London Underground)|Piccadilly]]
|Russell Square – Covent Garden
|Expected from Spring 2024<ref name=":12" />
|-
|[[Northern line|Northern]]
|Euston – Belsize Park
|November 2023
|-
|[[Central line (London Underground)|Central]]
|Holland Park to Bank
|February 2024
|-
|[[Northern line|Northern]]
|Golders Green – Hampstead
|Expected from Spring 2024<ref name=":13" />
|-
|[[Victoria line|Victoria]]
|Euston - Oxford Circus
|Expected from Spring 2024<ref name=":13" /> (as of April 2024 there is service on all Euston platforms)
|}