Functional classification

This information defines how a route should perform in serving the flow of traffic through a highway network. It is the grouping of highways, roads and streets by the character of service they provide and was developed for transportation planning purposes.

The Functional Classification Map Application allows users to view the federal functional classifications (FFC) for Washington state as defined and approved by the Federal Highway Administration (FHWA). The map is updated periodically. Changes in the functional classification system may be officially approved and not yet reflected on this site.

What is functional classification?

Functional classification is the grouping of highways, roads and streets by the character of service they provide and was developed for transportation planning purposes. Basic to this process is the recognition that individual routes do not serve travel independently in any major way. Rather, most travel involves movement through a network of roads. Comprehensive transportation planning, an integral part of total economic and social development, uses functional classification to determine how travel can be channelized within the network in a logical and efficient manner. Functional classification defines the part that any particular route should play in serving the flow of trips through a highway network.

FHWA Directive 23 CFR 470 states that the state transportation agency has the primary responsibility for developing and updating a statewide highway functional classification in rural and urban areas to determine functional usage of the existing roads and streets. The state transportation agency is to cooperate with responsible local officials, or appropriate Federal agency in the case of areas under Federal jurisdiction, in developing and updating the functional classification. The results of the functional classification is to be mapped and submitted to FHWA for approval and when approved serve as the official record for Federal-aid highways and the basis for designation of the National Highway System.

The Washington State Legislature in RCW 47.05.021 and the Federal-Aid Highway Act direct WSDOT to analyze the entire state highway system to classify and sub-classify all designated state highways according to their function and importance. For more information on federal guidelines please visit the FHWA website, Functional Classification Guidelines (Concepts, Criteria, and Procedures).

Functional classification revision process

The functional classification process is a cooperative effort involving the various local agencies, WSDOT regions, WSDOT local programs, metropolitan planning organizations, regional transportation planning organizations, multimodal planning division and FHWA.

Crosswalk table for referencing federal functional classification codes at WSDOT (PDF 385KB): This table crosswalks the old FFC codes to the 2010 FHWA FFC codes and the internal WSDOT FFC codes.

Functional classification process flowchart (PDF 22KB): This document will outline the basic steps in the functional classification change request process. Your Regional WSDOT Local Programs office can also assist with this process. Updated February 2018.

Functional classification change request form (WORD 74KB): All Functional classification requests must include the standard request form.

Guidelines for amending functional classification in Washington state (PDF 2,413KB): Development of new and/or changes of existing functional classifications are based on specific criteria found in this document.

Functional classification change request status (PDF 163KB): All current road change classification requests are found here. Last updated August 17, 2023.

Highway urban areas functional classification changes

Urban area adjustments

Federal law requires that Highway Urban (and Urbanized) Area (HUA) boundaries be reviewed and adjusted as necessary after each US decennial census. The Washington Adjusted Urban Area (AUA) process took place in the first half of 2013. A Boundary Review Team was assembled to oversee the process. The Federal Highway Administration (FHWA) approved the resulting HUA boundaries in summer 2013. The next urban area adjustments will be in 2023.

HUA functional classification changes

FHWA requires a functional classification review following adjustments to HUAs. All agencies affected by HUA changes must review their roads and streets within areas that have changed from rural to urban or urban to rural. Affected counties began their review of county roads on August 13th. On October 16th cities and MPO’s affected by the HUA changes were sent a request to review their roads and assess them for any changes necessary to their existing arterial or collector functional classifications. Arterial or collector classification changes resulting from the review need to be sent to our functional classification section. These changes should be listed, preferably in an Excel spreadsheet, and provided along with a map, showing the name of the roadway, beginning and ending termini, functional classification, urban or rural status, and the reason for the functional class change. All changes need to be submitted to WSDOT by December 5th.

Available reference maps

Reference maps showing the old and new urban boundaries are available as PDF’s and GIS shapefiles at this location:

  • Adjusted2013Sept09: GIS shapefile with the 47 new HUA’s (Urbanized and Small Urban).
  • Before2013Adjustments: GIS shapefile with the 35 old HUA’s (Urbanized and Small Urban).
  • UrbanRuralChangeMaps2013: Folder containing 49 urban area PDF’s with the old and new boundaries represented and boundary changes highlighted.
  • UrbanRuralStatusChange2013: GIS shapefile showing areas that are newly rural and areas that are newly urban.

Functional class change timeline

08/13/2013 - Initiate FC review process for county roads.
10/16/2013 - Initiate FC review process for city streets.
12/05/2013 - Complete the submittal of city and MPO FC change requests to WSDOT.
12/31/2013 - Approval of HUA FC changes by FHWA.

For functional class change submissions contact Mitch Vernon at 360-570-2441 by phone or email.

For general information contact Mark Bozanich at 360-596-8921 by phone or email.

2023 process will be coming soon

Functional classification data downloads

State route and non-state route arterials and collectors

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