Drivers in South King County will soon face tolls on a newly opened section of SR 509, with fees beginning at 5 a.m. Monday, Sept. 29, according to the Washington State Department of Transportation (WSDOT).
The one-mile tolled stretch runs between I-5 and 24th Ave South, just south of Sea-Tac International Airport.
Tolls will be charged in both directions at the I-5 ramps. Only the newly constructed expressway portion of SR 509 will require payment; existing sections of the highway remain free to use.
Vehicles with a Good To Go! pass will pay between $1.20 and $2.40, depending on the time of day. Drivers without an account will receive a bill by mail, with an additional $2 added to each trip. Carpools will not be exempt from tolls.
The toll road is part of the SR 509 Completion Project, which aims to ease congestion on I-5 and improve freight mobility between the interstate, the Ports of Seattle and Tacoma, and SEA Airport. The expressway’s first mile opened in late June.
Construction continues on the final two-mile extension, which will connect the expressway to where SR 509 now ends at South 188th Street. That section is expected to open in 2028.
WSDOT said toll revenue will be used to cover the costs of operating and maintaining the road, as well as help fund additional projects under the agency’s Puget Sound Gateway Program.
For more information on tolling and how to set up a Good To Go! account, visit MyGoodToGo.com.
