Editing Trans-Canada Highway (section)

=== Quebec ===
{{Main|Quebec Autoroute 40|Quebec Autoroute 20|Quebec Autoroute 85|Quebec Route 185|l2 = Autoroute 20|l3 = Autoroute 85|l4 = Route 185}}
[[File:Highway 20-Quebec.JPG|thumb|[[Quebec Autoroute 20]] eastbound]]
From Ottawa, the Trans-Canada Highway continues as a freeway and proceeds {{cvt|206|km}} east to [[Montreal]], as Highway&nbsp;417 in Ontario (and the Queensway in Ottawa) and {{lang|fr-CA|[[Quebec Autoroute 40|Autoroute&nbsp;40]]}} in Quebec.<ref name=Eastmap/> The Trans-Canada assumes the name {{lang|fr-CA|Autoroute Métropolitaine}} (also known as "The Met" or "Metropolitan Boulevard") as it traverses Montreal as an elevated freeway. At the Laurentian interchange, in Montreal, the Abitibi route (Highway&nbsp;66, Route&nbsp;117, A-15) rejoins the main TCH line. The TCH then follows [[Quebec Autoroute 25|Autoroute&nbsp;25]] southbound, crossing the [[Saint Lawrence River|St. Lawrence River]] through the 6-lane [[Louis-Hippolyte Lafontaine Bridge–Tunnel]], and proceeds northeast on [[Quebec Autoroute 20|Autoroute&nbsp;20]] for {{cvt|257|km}} to {{lang|fr-CA|[[Lévis, Quebec|Lévis]]|italic=no}} (across from [[Quebec City]]).

East of {{lang|fr-CA|Lévis|italic=no}}, the Trans-Canada Highway continues on Autoroute&nbsp;20 following the south bank of the St. Lawrence River to a junction just south of {{lang|fr-CA|[[Rivière-du-Loup]]|italic=no}}, {{cvt|173|km}} northeast of {{lang|fr-CA|Lévis|italic=no}}. At that junction, the highway turns southeast and changes designation to [[Quebec Autoroute 85|Autoroute&nbsp;85]] for {{cvt|43|km|}}, and then downgrades from a freeway to [[Quebec Route 185|Route&nbsp;185]], a non-Autoroute (not limited-access) standard highway for {{cvt|9|km|}} until [[Saint-Louis-du-Ha! Ha!]], where Autoroute 85 resumes once again. The portion from Autoroute&nbsp;20 to [[Edmundston]], New Brunswick, is approximately {{cvt|120|km}} long.<ref name=Eastmap/>

Since the Trans-Canada Highway for the most part follows Quebec's Autoroute System, which is always composed of a minimum four-lane freeway, travel through Quebec is generally, safe, fast, and congestion-free.{{citation needed|date=June 2023}} The exception is the route through Montreal, which can be prone to traffic congestion. However, drivers can bypass the city on the [[Toll highway|tolled]] Autoroute 30, which is not part of the Trans-Canada.

The maximum speed limit on the Quebec Autoroute System (including the TCH) is a strictly-enforced {{cvt|100|kph}}. However, the speed limit may be lower in select spots, such as through tunnels or major interchanges.

Since 2018, Quebec has been working on upgrading the {{Convert|40|km|mi|-long|abbr=out|adj=mid}} two-lane section of Trans-Canada Highway along [[Quebec Route 185|Route&nbsp;185]] to an Autoroute, with {{Convert|21.5|km|abbr=on}} of new freeway commissioned during 2021–22, another 10 km in 2024 and the remaining {{Convert|8.5|km|abbr=on}} of freeway under construction, with final completion targeted for 2026.<ref>{{Cite web |title=Réaménagement de la route 185 en autoroute (85) |trans-title=Redevelopment of Route 185 by Autoroute 85 |url=https://www.quebec.ca/transports/projets-routiers/bas-saint-laurent/reamenagement-route-185-autoroute-85 |access-date=April 30, 2024 |publisher=Gouvernement du Québec |language=fr |archive-date=April 30, 2024 |archive-url=https://web.archive.org/web/20240430135305/https://www.quebec.ca/transports/projets-routiers/bas-saint-laurent/reamenagement-route-185-autoroute-85 |url-status=live }}</ref>{{Update after|2024|12|reason=Update length as the remaining segments complete over the next few years}} Once this project is complete, the disconnected sections of Autoroute 85 will be joined, and all of Quebec's Mainline Trans-Canada Highway route will be minimum four-lane freeway standards. This will also result in the TCH becoming a continuous freeway from Arnprior, Ontario, to [[Lower South River, Nova Scotia]].