2.3 Street Classification

Last Updated: 6-17-2017Print page

2 Street Type Standards

Seattle is required by state law to classify city streets into primary functional classifications, which are generally based on the American Association of State Highway and Transportation Officials (AASHTO) standards. The AASHTO standards that apply to urbanized areas that have over 50,000 people are used.

The City builds upon the AASHTO functional classifications by also identifying more refined Traffic Classifications, which further define the roadway network according to different levels of emphasis on mobility versus direct access to property. Seattle’s functional classifications include Interstate Freeways; Regional, Principal, Minor and Collector Arterial streets; Commercial and Residential Access Streets; and Alleys. At one end of the hierarchy, a freeway emphasizes traffic movement, while restricting access to adjacent land. At the other end of the hierarchy, a residential access street provides easy access to adjacent residential, commercial, and industrial land uses, while limiting traffic passing through to other destinations. The arterial network is the “backbone” of the roadway system and accommodates the most trips for all modes.

The City of Seattle street classification network are modified periodically. Any changes to traffic classifications are adopted by City Council Ordinance. Please confirm the classification of streets adjacent to a site by referencing the Street Types map. 

Table 1 summarizes Seattle’s Street Types and the land uses and associated street classification(s).

  STREET TYPE

  ADJACENT LAND USE AND INTENSITY

TYPICAL STREET CLASSIFICATION

Downtown
  • Located within the Downtown Urban Center
  • High intensity office, commercial and ground floor retail with moderate levels of high rise residential

Principal Arterial

Downtown Neighborhood
  • Located within the Downtown Urban Center
  • Moderate intensity office, commercial and high rise residential with ground floor retail

Minor and Collector  Arterials

Downtown Neighborhood Access
  • Located within the Downtown Urban Center
  • Moderate intensity commercial, midrise residential, with ground floor retail

Non-arterials

Urban Village Main
  • Located within Urban Village or Centers (except Downtown)
  • High intensity retail, moderate intensity commercial and office and low to mid-rise residential

Principal Arterial

Urban Village Neighborhood
  • Located within Urban Village or Centers (except Downtown)
  • Moderate intensity retail, low intensity office and low to mid-rise residential

Minor and Collector Arterial

Urban Village Neighborhood Access
  • Located within Urban Village or Centers (except Downtown)
  • Predominantly low to mid rise residential with sporadic ground floor retail

Non-arterials

Urban Center Connector
  • Located outside of Urban Villages or Centers; serves Transit and/or Freight Networks
  • Medium to high intensity residential, commercial, institutional, ground floor retail

Principal and Minor Arterial

Neighborhood Corridor
  • Located outside of Urban Villages or Centers; does not serve primary transit or freight network
  • Predominantly low to medium intensity residential and sporadic retail, commercial and office

Principal, Minor and Collector Arterials

Industrial Access

Principal and Minor Arterials

Minor Industrial Access

Non-arterials

Neighborhood Yield
  • Residential streets located outside Urban Villages and Centers
  • Low intensity residential

Non-arterials

Commercial Alley
  • Located within Urban Villages and Centers
  • High to moderate intensity commercial, office and residential
  • Primary use is to serve loading needs

Alley

* Exceptions may apply.