Autoroutes are identified by blue-and-red shields. The red header of the shield contains a white image representing a highway overpass, and the blue lower portion of the shield contains the Autoroute's number in white, along with a fleur-de-lis, which is a provincial symbol of Quebec.
Most Autoroute signs in the province are in French, though English is used on federally-financed or -owned routes, such as the Bonaventure Expressway in Montreal. To surmount the language barrier, however, most signs in Quebec use pictograms and text is avoided in most cases, with the exceptions usually only being the names of control cities. Other exceptions that are posted in both languages is the illegal use of radar detectors when entering the province that reads "RADAR DETECTORS PROHIBITED", as well as areas where roads can be slippery due to melting ice and snow, marked "DEGEL / THAW".
Autoroutes are divided into three types – principal routes, deviation routes, and collector routes – and are laid out and numbered in a fashion similar to the Interstate Highway System in the United States. The principal Autoroutes are the major highways of the province, and have single- or double-digit numbers. East-west Autoroutes running parallel to the Saint Lawrence River (for example, Autoroute 20 and Autoroute 40) are assigned even numbers, while north-south Autoroutes running perpendicular to the Saint Lawrence (such as Autoroute 5 and Autoroute 15) are given odd numbers. Deviation and collector Autoroutes both feature triple-digit numbers. Deviation routes are bypasses intended for truck traffic to circumvent urban areas, and are identified by an even number prefixing the number of the nearby Autoroute that it bypasses (for example, Autoroute 440 in Laval). Collector Autoroutes, by contrast, are spur routes into urban areas, and are identified by an odd number prefixing the number of the nearby Autoroute that it branches off of (such as Autoroute 720, a spur of Autoroute 20 into downtown Montreal).
Quebec's first Autoroute was the Autoroute des Laurentides (Laurentian Autoroute), which opened in 1959 as a toll road. This initiative to bring freeways into Quebec was started by Maurice Duplessis, whose government saw the construction of the Laurentian Autoroute (now A-15) from Montreal to Saint-Jérôme and the first section of the Boulevard Métropolitain (A-40), which opened in 1960.
It was the Quebec Liberal government of the 1960s that saw the construction of further Autoroutes, with a grid numbering system and the introduction of the blue and red shield. The sign is inspired by the American Interstate sign. This was especially needed in light of the fact that many visitors would be flocking to Montreal by car for Expo 67. Montreal's Autoroute Décarie (A-15) and the Louis Hippolyte Lafontaine Bridge-Tunnel were constructed for that very reason. The Autoroute des Cantons-de-l'Est (Eastern Townships Autoroute - A-10) opened in 1964, and its continuation, A-55 between Magog and Rock Island, opened in 1967, connecting with Interstate 91. What are now the A-20 (part of the Trans-Canada Highway) and the A-15 to New York (connecting with Interstate 87), originally built in the 1940s, were upgraded to expressway standards. The A-20 also connects with Highway 401 in Ontario. A-40 was extended out to Berthierville, and later to Trois-Rivières in the 1970s. Others include Autoroutes 25, 30 (southern beltway), 31, 35 (eventually connecting to Interstate 89), Autoroute Laurentienne (73), and 640 (an unfinished proposed northern beltway).
The 1970s also saw the completion of the Pierre Laporte Bridge in Quebec City, connecting the south shore of the Saint Lawrence River to the north. In addition to this, the A-73 was extended to Beauce, the A-20 was extended to Rivière-du-Loup, and the Chomedey Autoroute (A-13), the A-19 and the A-440 were constructed in Laval. Autoroutes were built (two sections of A-440, and A-740) and a few more planned in the Quebec City region, creating a dense web, which led to significant sprawl. During the 1970s, the Parti Québécois came to power, whose platform mandated an expansion of public transportation over the construction of more Autoroutes. Existing Autoroutes were extended (e.g., the A-40 was extended from Trois-Rivières to Quebec City) but no new Autoroutes were built.
The Autoroute des Laurentides, the Autoroute des Cantons-de-l'Est, the Autoroute de la Rive-Nord (North Shore Autoroute), and the A-13 were toll roads until the mid-1980s, when the toll barriers were removed and the province stopped collecting tolls from vehicles using the Autoroutes. The last toll booth was on the Champlain Bridge. It was later removed because the Champlain Bridge is federal property and is thus not subject to provincial tolls.
In the 2000s, there were several high-profile failures and collapses around some Autoroutes, due to aging and crumbling infrastructure, including the Boulevard du Souvenir overpass collapse, De la Concorde overpass collapse, and most recently the Ville-Marie tunnel collapse. An online poll by Léger Marketing conducted shortly after the Viger tunnel collapse found that 88 percent of Montrealers are “worried” about the state of roads, bridges and tunnels in the city, with more than half of respondents saying they are downright “scared” to drive under an overpass (58 percent), on a bridge (54 per cent), or through a tunnel (53 per cent). McGill University’s Saeed Mirza stated that ill-advised design choices and poor-quality concrete were used in the construction rush ahead of Expo ’67 and the 1976 Olympics. In particular, the concrete used was permeable with lack of proper drainage, and these allowed chlorides from de-icing salts to corrode the steel reinforcements.
History: First opened in 1964, from the bridge to Route 105 (Gatineau, Exit 5); another section opened in 2009 from chemin de la Rivière (Exit 13 to 21) to an intersection with Route 105 further north near Farm Point. In 1993 an isolated divided four-lane section of Route 366 existed in La Pêche, which was connected to the existing A-5 in October 2014, extending A-5 to 33 km in length. This section has A-5 as well as Route 366 signposts.
History: First section (Montreal-Longueuil across the Champlain Bridge) opened in 1962. Much of A-10 opened in 1964 as a toll road, with the completion of the Eastern Townships Autoroute.
Notes: The portion east of Autoroute 55 (linking that autoroute with Route 112) was renumbered as Autoroute 610 on September 29, 2006. 
Future: The Autoroute Bonaventure will be completely reconfigured in the coming years. The Société du Havre de Montréal has proposed transforming the autoroute into an urban thoroughfare as part of a broader project to redevelop Montreal's harbourfront. In addition, a current proposal to build the East-West Highway across central and northern Maine calls for the A-10 to be extended to the U.S. border at Coburn Gore where it would meet the new highway. Doing so would create a new and more direct limited-access highway link between Maine, the Maritime Provinces, and Quebec.
History: the autoroute is parallel to the Decarie Boulevard (hence the name); from Côte-de-Liesse to Queen Mary Road on the south, it was built on a wide expanse of vacant land, donated to the City by the Décarie estate on the condition that only a streetcar line be established. When the streetcar system was dismantled in 1959, it was an obvious right-of-way for a highway, so the Décarie autoroute was dug there. South of Queen Mary Road, however, were a significant number of houses which were demolished. In order to avoid demolishing the Notre-Dame-de-Grâces church, the highway veers west south of Côte-Saint-Luc, and runs between Appleton and Botrel Streets, all the way to Saint Jacques Street, where it spectacularly goes from below-ground to well above ground as it intersects with Autoroutes 20 and 720 in the infamous Turcot Interchange (dubbed "Spaghetti Junction" by train crews operating the CN Rail Turcot Yard). Following the conversion from streetcar line to highway, the Décarie Estate unsuccessfully sued the city but was unable to prevail because they did not document their case well enough for the nevertheless sympathetic court.
History: First section was opened in 1970 (boul. H-Bourassa to boul. Lévesque),the final section was completed twenty years later.
Notes: Most of the section in Montreal is an urban arterial (Avenue Papineau). It was originally meant to be the eastern counterpart of Autoroute-15, connecting with the Jacques-Cartier Bridge, but it was decided not to gut yet another swath of housing within the City of Montreal. The portion south of Autoroute-40 no longer occurs as part of A-19.
The extension north of A-440 was not assigned to A-19 but Route 335 north of A-440 was shifted onto it from boul. des Laurentides.
Notes: Autoroute 20 is composed of two separate segments. The western segment extends from the Ontario border to L'Isle-Verte, and the eastern segment is a bypass of Rimouski, which was extended in 2003 to Luceville and in 2008 to Mont-Joli. A section of this highway from Vaudreuil-Dorion eastward to the Galipeault Bridge (approximately 4 miles or 6.4 km) is a congested arterial four lane road. It is slowly being upgraded to Autoroute standard.
Future: There are plans to connect both segments - extending the eastern segment to Trois-Pistoles and eventually connecting with the Rimouski bypass.
This autoroute has the peculiarity of having a railroad crossing at grade in Saint-Hyacinthe, immediately east of the Boulevard Laframboise overpass. For this particular crossing, the Code de la sécurité routière du Québec has been amended to allow buses to cross this crossing without making the customary mandatory stop. Train crews are instructed in their special operating instructions to call the Sûreté du Québec police to stop the traffic before crossing the highway.
Name: Autoroute Transcanadienne (or, unofficially, Autoroute Louis-Hippolyte-La Fontaine and Autoroute de Lanaudière)
Description: The A-25 was divided into two sections: the first section connected the A-40 to the A-20 (Louis Hippolyte Lafontaine Bridge-Tunnel) and the second ran from the Pie-IX Bridge to Route 125 in Saint-Esprit. Since May 2011 these sections have been joined, and the section from Pie-IX to the new interchange lost its A-25 designation (approx. 5 km / 3.1 mi).
Length: 52.1 km (32.4 mi)
History: The first section was completed in 1967 and is a part of the Trans-Canada Highway while the second section was completed up to Saint-Esprit in 1999
Future: There are long-term plans to extend A-25 all the way to Route 347 in Notre-Dame-de-la-Merci which would double its length to 100 km. A section of Route 125 is currently expressway-grade, which would form the northern end of A-25, connected by 30 km of new highway. No timeline is currently set.
History: First segments opened in 1968, followed by more in 1971, 1972, 1975, 1977, 1982 and 1996 to form the main section from Sorel-Tracy to Autoroute 15; the Valleyfield bypass opened in 1976, the Bécancour section in 1975, and the Kahnawake bypass in 1990. A new alignment bypassing Saint-Constant south of Route 132 was built to Autoroute 15, opening in November 2010, and directly linked to the east in November 2011. Construction has been completed on the new section between Châteauguay and Vaudreuil-Dorion and joined the other part in December 2012. The existing A-30 segment south of Salaberry-de-Valleyfield has been renumbered as A-530 and connects with A-30 just south of the new A-30 bridge over the Saint Lawrence River. Now finished, A-30 provides a much needed and long awaited southern bypass of Montreal. However, there are no current plans to build the "missing link" of A-30 between Sorel-Tracy and Bécancour.
Description: A short Autoroute that connects Saint-Jean-sur-Richelieu and Iberville (now forming one city) to the A-10; it was briefly designated as the Autoroute de la Nouvelle-Angleterre but the name was revised before any signs were posted. A-35 ends at Route 133, which continues to the Canada/U.S. border where it connects to Interstate 89.
Future: A-35 will be extended to finish the freeway link to I-89 via some new alignments and upgrading of certain expressway sections of Route 133. Some have also called for a northern extension to Sorel-Tracy, although there are no current official plans for that.
History: The A-40 is a part of the Trans-Canada Highway from the Ontario border to the A-25 interchange. The first section of the Autoroute Métropolitaine opened in 1960. The Autoroute Métropolitaine was originally intended to be below-ground, like the Autoroute Décarie is. But as sewers run on a north-south axis, this would have called for expensive sewer rerouting below the excavation through inverted siphons. Thus, it was decided to build an elevated autoroute, with one notable exception in the Town of Mount Royal, to separate the residential suburb from the industrial area to the north.
Future: It is envisioned that A-40 will be extended eastward, possibly as far east as Route 360 or even Route 362 in La Malbaie, as recreation in the Charlevoix area increases. There are no current official plans to extend A-40, however, and upgrades of Route 138 are more likely.
Description: The A-50 is a recently completed route; in the East it ends at Route 117 near Mirabel, connects the A-15 and Mirabel Airport to Route 148 at Grenville just west of Lachute, near a bridge over the Ottawa River to Hawkesbury, Ontario—this section includes an at-grade railway crossing. The A-50 starts in the west to link downtown Hull (part of Gatineau) to Thurso just east of Buckingham, and now continues east without any gaps.
Original Planned Length: 290 km (Fort-Coulonge via Hull to Montréal).
Revised Length: 159 km (Gatineau (Hull) to Mirabel).
History: The western section of this Autoroute was originally named the Autoroute de l’Outaouais, as it ran within the Outaouais Region from Hull to Buckingham and follows the path of the Ottawa River (Rivière des Outaouais) on the Quebec side.
The expressway was officially announced in 1965 to link the Outaouais and the Montréal area without crossing into Ontario, plans were altered several times to reduce the number of farms affected by the road and detoured north to connect to the planned end of A-13 (which was never completed past A-640) and to facilitate access from Ottawa-Hull to the planned International Airport at Mirabel (built and in operation from 1975 until 2004, but currently unused by travelers). The original plan called for A-50 to be extended east as A-40 near Berthierville, and for a brief period in the 1970s and early 1980s, a "super-2" section of Route 158 was signed as A-50.
Except for the western part linking downtown Hull to Buckingham, and some short segments near Lachute and Mirabel Airport to A-15, the expressway is actually a high speed (100 km/h) 2-way road. Overpasses are built to accommodate a future divided highway but currently only one portion of the overpass has the 2-way A-50 going underneath them.
Future: A-50 is now completed between the western side of Hull's downtown to A-15 and Route 117 at Mirabel, closing the remaining 55 km gap in the freeway between Thurso and Grenville. Slight westward extensions are also possible (but not planned), however it is very unlikely to extend beyond Aylmer (now part of Greater Gatineau) to Fort-Coulonge or the rural parts of the Pontiac in the Western Outaouais region. The road therefore starts near kilometre number 133 in the West and terminates at kilometre 292 in the East.
Extensions opened in October and November 2008 to add some 15 km to Thurso on the west segment and some 13 km from Grenville on the east segment. Two other segments opened in August and October 2011 adding 30 km to the eastern part. Work is now finished on the last remaining segment; it opened on November 26, 2012.
History: The first section of what is now the A-55 was opened in 1967, serving as a continuation of the Autoroute des Cantons-de-l'Est (Eastern Townships Autoroute) between Magog and Rock Island, connecting with Interstate 91.
Notes: A section of A-55 south of Drummondville was planned to be part of A-51; A-55 was to continue south along the current A-955 alignment before veering west. Some sections remain a Super-2, although those are currently being twinned.
Future: There are plans for Autoroute 70 to be extended from Jonquière to Alma, and eastward from Chicoutimi to La Baie, however, the official government construction time-table has no indication of when this might be.
History: The newest Autoroute, officially designated in December 2005. Replacing Route 185. Part of the Trans-Canada Highway.  A short freeway section, less than 2 km in length, had already been constructed at A-20 but only designated as Route 185. Other sections of Route 185 are being built to freeway standards (discontinuously) and A-85 shields are going up on them.
Future: Additional construction is planned to complete A-85 to the New Brunswick border to connect with Route 2 and to fill in remaining gaps.
History: Completed in 1978. Renamed in 2007 after the death of Jacques O'Bready, the former mayor of Sherbrooke.
Future: Autoroute 410 is planned to connect with Route 108 just east of Lennoxville, allowing truck traffic to completely bypass the congested town. It will pass south of the town, before connecting near the experimental farm to the east.
History: Was part of Autoroute 10 until September 29, 2006. Renamed in 2008 in honour of Louis Bilodeau, a former local television personality.
Future: A current proposal to build the East-West Highway across central and northern Maine calls for the A-610 (its original numbering as A-10 restored) to be extended to the U.S. border at Coburn Gore where it would meet the new highway. Doing so would create a new and more direct limited-access highway link between Maine, the Maritimes, and Montreal.
Description: This Autoroute passes under DowntownMontreal through the Ville-Marie tunnel, but the length of the route runs from the Turcot interchange up to the Jacques-Cartier Bridge. The A-720 becomes an urban boulevard called "Ville-Marie" at the bridge and later merges with rue Notre-Dame.
Length: 8.5 km (5.3 mi)
Expansion: A planned upgrade to rue Notre-Dame will make an urban boulevard stretch from the bridge to the A-25. A future project includes upgrading rue Souligny into the A-720 at A-25, taking the load off Notre-Dame at and across the A-25.
History: It was originally envisioned that Autoroute 20 would extend from the Turcot Interchange, along the route of A-720, to the Louis Hippolyte Lafontaine Bridge-Tunnel but those plans were cancelled years ago. They have been resurrected recently by the Quebec provincial government despite the opposition of the Montreal city council, which favours conversion of the Notre-Dame street into an urban waterfront boulevard instead.
Description: This route is the new designation of what was the section of A-30 bypassing Salaberry-de-Valleyfield, which has been extended east to where a new bridge across the St. Lawrence River has been constructed.
Length: 14 km (8.7 mi)
History: Until the end of 2012 most of the route was signed as A-30, with a short section unfinished where the A-530/A-30 interchange was built. A-530 was completed and designated in 2012.
History: This short section of Autoroute was destined to become part of a much longer section of freeway, as the A-55 was supposed to follow this route south towards Warwick and Richmond, as opposed to its current alignment through Drummondville; however, this was never realised, but the short route still remains.
Note: None of this highway is of freeway standard, so it would not even be considered a super-2.
History: Planned in the 1960s, A-6 was to roughly parallel Route 104. The western half of the route was canceled by the mid-1970s. The rest of the route was killed a few years later. Reconstruction of A-15 through La Prairie in the mid-2000s removed a grassy median at km 49 where ramps were to be built for a directional T-interchange to connect with A-6.
History: Planned in the 1960s and early 1970s, A-9 was to provide a fixed crossing over the Ottawa River. Evidence of the proposed A-9 can be found in the form of a wide median on A-40 (to accommodate a Y-interchange) just east of Exit 1 in Pointe-Fortune.
Autoroute 55 south of Autoroute 20 to Route 116 was co-designated Autoroute 51 until 1982. By 1983, official documents had removed the A-51 designation from that section of A-55. In the 1970s, there were plans to extend A-51 north of A-20 to a proposed easterly extension of A-30 near Yamaska.
Name: Mount Royal Autoroute (referred as the Northern leg of the downtown loop) (unbuilt)
Description: Downtown Montreal expressway loop (short spur route) that included the Decarie (A-15), Ville Marie (A-720), and Papineau (A-19) autoroutes.
Length: 7 km (4.3 mi), 3 km (1.9 mi) of those 7 kilometres planned as a tunnel under Mount Royal.
History: In its 1960 master highway plan, the Montreal Metropolitan Committee proposed a new 7 km (4.3 mi) long autoroute along the city's east-west street grid at the northern edge of downtown. The six-lane autoroute was forecast to handle as many as 4,500 vehicles per hour during weekday peak periods. Beginning at the Decarie Autoroute at Monkland Avenue in the Notre-Dame-de-Grâce section of the city (at the current EXIT 66 on A-15), the Mount Royal Autoroute was to extend in a northeasterly direction through Westmount underneath Mount Royal Park before emerging above ground at Rachel Street connecting to the unbuilt A-19 Montreal section of what is now Papineau Avenue.
Description: Eastern terminus: Autoroute de l'Outaouais (A-50); Western terminus: Britannia Bridge (unbuilt) (Ottawa/Gatineau-Aylmer border)
History: This freeway would have served as a bypass of the City of Gatineau and would have been a link across the Ottawa River to Highway 416 in the west end of the City of Ottawa. It also would have made Autoroute 50 and Autoroute 5 movements easier. However, the Quebec Ministry of Transportation stated in 1996 that there was no need for a City of Gatineau bypass, but it is keeping the corridor for a possible future boulevard or freeway in partnership with the National Capital Commission. The plan calls for construction of a bridge (Britannia Bridge) crossing the Ottawa River.