Functional Classification and State Aid

James K. Polk Building, Suite 900
505 Deaderick Street
Nashville, Tennessee 37243-0344 

Functional Classification is the process by which streets and highways are grouped into classes, or systems, according to the character of service they are intended to provide. Systems Section is responsible for the determination and classification of the individual roadways. This office is the administrator of the official Functional Classification Map for the State of Tennessee and all documentation pertaining to any and all changes to the system. This office is also the connection for all changes in the Functional Classification System. For more information, contact the community transportation planner in your region.

State Highway Designation: It is the responsibility of the Highway Systems Office to designate the identifying number of all new state routes. The official documents identifying the route revisions, additions and deletions are maintained in this office. For more information about the designation process, contact the community transportation planner in your region.

National Highway System: The National Highway System (NHS) includes the Interstate Highway System, as well as other roads important to the nation's economy, defense, and mobility. The NHS was developed by the Department of Transportation (DOT) in cooperation with the states, local officials, and metropolitan planning organizations (MPOs).

The Highway Systems Office maintains the official mileage for the NHS in Tennessee. Any changes in the system are initiated in this office. For more information, contact the community transportation planner in your region.

For more information on the National Highway System, visit the Federal Highway Administration website.

For additional information regarding Functional Classification and State Aid, please contact TDOT Policy Office Supervisor Dr. Casey Langford by phone at (615) 532-5824 or by email at