Canada/Tagging guidelines/Road classification

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This page documents Canadian road classification standards for determining which value of highway=* should be used for various roads.


This classification guidelines is being a revision on the guidelines that have been in place since the beginning of the Canada mapping project, which are as follows:

  • highway=motorway - controlled-access highways (freeways/autoroutes)
  • highway=trunk - NHS core routes that aren't controlled-access (with exceptions). While largely used for that in most of the country, this tag is used to indicate expressways in parts of the country (similar to the older road classification guidelines for the United States), especially in Ontario and Quebec.
  • highway=primary - Upper-tier provincial highways. Major arteries in urban areas, usually an urban section of provincial highway or a former provincial highway.
  • highway=secondary - lower-tier provincial highways and Ontario county and regional roads. Most other arterial roads in urban areas.
  • highway=tertiary - urban and rural roads that neither fit secondary or unclassified
  • highway=unclassified - most rural roads, and urban streets that aren't residential or is mixed-use
  • highway=residential - residential streets

The trunk network under the scheme is by the most part, well connected, but since mappers in the United States have undertaken a major attempt to revise road classification guidance, which has been adapted in various states, a partial revision to coordinate Canadian highway mapping with the reclassifications being done south of the border is necessary, especially to address existing and anticipated classification gaps at the border. The revision will largely be similar to those adopted south of the border, but will take Canadian considerations into account.


Canadian tagging practice largely follows an importance-based approach, but is combined with one-to-one correspondence to highway type indicated by the design of route number signage or number series. The National Highway System includes most freeway-grade routes and roads of strategic importance that are selected for eventual improvement and upgrading by the respective provincial and territorial governments with federal coordination in funding.

On particularly important principle is connectivity. With exceptions such as terminal topography ("land's end", remote northern areas), roads tagged motorway to tertiary should form a contiguous network without dangling spurs or disconnected "islands". Roads should not be downgraded because of reduced vehicular capacity, lower construction quality, or change in authority behind maintenance or numbered highway type (e.g. Connecting Links, reliquishment to local control, different highway type in another province or US state).


Ontario Highway 401 in the GTA, an example of a motorway

As the topmost category, highway=motorway should have all these characteristics listed below. These do not need to be a divided highway/dual carriageway, but most should be.

  • Access control (entry and exit only via on-/off-ramps). Pedestrians, bicycles and slower vehicles are generally prohibited, and generally signed as such at entry points, but in the Prairies (Alberta, Manitoba, Saskatchewan), it is not indicated at all.
  • No intersections and traffic lights (on-ramps or ends may have one though)
  • No driveways (excluding those for highway maintenance)
  • Highest design standards to sustain high speeds across long distances as part of an interconnected network.

Roads that meet this criteria includes the Ontario 400-series highways, Toronto expressways (Gardiner, Allen and the DVP), Quebec autoroutes, and most Nova Scotia 100-series routes. In most other provinces, there are parts of the highway network that are partially or completely built to freeway standard but do not form a distinct network like those aforementioned or are not marked with prohibitory signs at entry points; what can be a motorway can be subjective, and can be a source of edit wars.

Roads that are not part of a contiguous motorway network and exhibit motorway-like characteristics for a short distance should not generally be classified as motorway. In general, a disconnected motorway segment should have multiple, grade-separated and controlled-access highway interchanges (2 or more being a rough benchmark used in Canada) for a significant distance, usually 3-15 km, to be tagged as a motorway.


Saskatchewan Highway 1 (Trans-Canada Highway), an example of a trunk road

As the topmost non-motorway classification, highway=trunk should be applied the most important non-motorway routes that provide the main route for long-haul traffic between population centres of regional importance. Examples are the majority of the Trans-Canada Highway, the Yellowhead Highway, the Alaska Highway, and Ontario Highway 17. Construction can vary, from two-lane highways with paved shoulders and occasional passing lanes, to divided expressways with occasional interchanges.

In previous Canadian practice, highway=trunk is mostly applied to the non-motorway core routes of the NHS, but it has been applied to some roads in some provinces (notably Ontario, Quebec and New Brunswick) that are built to expressway standard, between an ordinary arterial road and a freeway, which is also adapted as the standard for urban trunk roads in the United States under the 2021 scheme. Under the revised Canadian scheme, other routes will be added in addition to the NHS core routes to highlight other links between key cities.

Expressways should generally be classified according to their relative importance and connectivity, and tagged with expressway=yes.

In some cases, two population centres may be served by more than one route with similar vehicle transit times. In general, the trunk route should:

  • Represent the "best" route between the population centres when all factors are considered
  • Minimize change in numbered routes or use of off-route "shortcuts"
  • Favour a route that has the "best" continuity/connectivity with the rest of the road network
  • Favour bypasses for faster travel through built-up areas.


As the second highest non-motorway classification, highway=primary should apply to high-importance roads that do not fit trunk or motorway. This includes most upper-tier provincial highways that are neither motorway nor trunk. In Ontario, these can also include former provincial highways, and in areas of high population density, these can be a arterial road which has a higher traffic volume or construction standard, or is a former provincial highway (e.g. segments of the Edmonton inner ring road, the former Highway 6 through downtown Regina, some unnumbered arterial roads in Metro Vancouver such as Boundary Road, Marine Way and Fraser Highway). These generally have higher traffic volumes compared to roads of similar construction in the area.


highway=secondary should generally apply to minor arterial roads in both urban and rural areas. This includes lower-tier provincial highways (Alberta highways 501-986, Manitoba provincial roads, Northern Ontario secondary highways, most Quebec 200 and 300-series highways, Saskatchewan secondary highways and numbered municipal roads), most Ontario regional or county roads, and most urban arterial roads. Rural secondary roads are usually paved, two-lane highways with no shoulders, but these can vary from gravel roads to a two-lane with paved shoulders and occasional passing lanes. Urban secondary roads are usually divided or multilane arterial roads and have higher posted speed limits that other roads in the area.


highway=tertiary should generally apply to both urban and rural roads that are not as important to be classified secondary but is more important than roads that are tagged unclassified or residential. What is a tertiary varies by province, but these are generally maintained by the local municipality. In Ontario, these are tertiary highways (800 series) in Northern Ontario and minor county/region/district roads elsewhere in the province. In urban areas, these can either be smaller minor arterials or collector roads. These are usually prioritized for snow removal over other roads.

Urban tertiaries usually has these characteristics:

  • Narrow: usually two lanes, and no more than 4 lanes. Usually not divided. May or may not have a painted centreline
  • Local: broken up by rivers, freeways and railways
  • Traffic-calmed: lower speed limit than surrounding secondaries, usually has school and playground zones, more traffic lights, roundabouts, splitter islands or other traffic calming measures at intersections, more winding alignments.

Rural tertiaries usually branches from a secondary highway to serve a notable settlement or is an alternate route to highways. They are usually paved, but they do not need to, especially if the tag is used to distinguish a more significant unpaved local road from other similar ones.


highway=unclassified should generally apply to most other roads in rural areas, and most streets that aren't residential or are mixed-use in nature in urban areas.


highway=residential should be used for roads primarily used to access homes

Provincial and territorial classification standards

The Territories will generally not need any necessary overhaul.

Province Highway classification Documentation update status Top-level reclassification Notes
Alberta Alberta/Highway classification draft
British Columbia British Columbia/Highway classification draft Some roads crossing to Idaho and Washington state already upgraded to trunk.
Manitoba Draft:Manitoba/Highway classification not started
New Brunswick
Ontario Ontario/Highway classification draft
Quebec not started
Saskatchewan Saskatchewan/Highway classification draft

External discussions

  • talk-ca Proposed changes to road classification and related stuff

Project process

The process will be similar to those being done in the United States, and is at the province level.

  1. Read and digest this page, and learn its principle
  2. Prepare a draft page for your home province that reference this page
  3. Contact mappers in your province and get feedback.
  4. Once there is local buy-in in the draft, update the province page to reflect the new guidelines
  5. Begin retagging highways to reflect the new guidelines

Preparing province-level draft

Anyone can start the reclassification process by writing a draft page for one's province that reference this page. The page can be named [Province name]/Highway classification, but you can place the draft on your user space if you prefer.

The Ontario/Highway classification is one fairly complete example, but see the other provinces' drafts to get a sense of details specific to each province, as well as differing official classification schemes and urban/rural differences.

Important population centres

In each province-level page, a useful part is to define the most important population centres that should be connected to the top-level highway network. This should include places within and outside the province (including territories and US states).

Centres of census metropolitan areas (CMAs) should generally qualify as important population centres, especially in denser regions. In sparse and remote regions, one good rule of thumb is these should generally be control cities used in direction signs at important highway junctions and mileage signs after each junction.

From there, identify the "best" routing between the cities. Often, these routes will be following NHS routes, but these may not necessarily be the case especially in the Prairies. In places such as Southern Ontario, the "best" route will often be on freeways. Utilize additional supporting data (see below)

Supporting data

The provincial guidelines should include supporting data (functional classification, NHS, service class, traffic counts, etc.) that can help determine why one route should be considered to be better than others in providing connections between provinces, regions or cities. Not all provinces publish those data, and as such information can contradict each other, we use those for reference and those are weighed against each other. That said, most provinces have their numbered highways subdivided into number series that indicate implied importance to traffic, and the classification be easily determined through those info indicated in the number or the shape of the shield.

Lists/map of NHS routes can be found in the Council of Ministers of Transportation (COMT) website, but these can also be in provincial government web portals in certain provinces. NHS routes are categorized as either Core, Feeder, Intermodal Connector or Northern and Remote; most Core routes and some feeder routes should qualify for trunk, but that should be treated as a rough rule of thumb than an absolute guideline.

Contacting other mappers and gaining consensus

Wrapping up documentation