The new SR 509 Expressway opens soon!

Try it free through summer.

Save $2 on each toll in Washington with a Good To Go! pass

An alternate route

The first mile of the new SR 509 tolled expressway runs between I-5 and 24^th Avenue South in south King County. The last two miles (extending to South 188^th Street) will open in 2028.

SR 509 Completion Project benefits

Help manage congestion by providing freight an alternative route to the ports and industrial areas by SeaTac.
Make it easier to get to Seattle-Tacoma International Airport from the south.

Things to know:

No toll on existing routes: You'll still be able to use the routes you take today without paying a toll, including the existing SR 509 north of South 188^th Street.

Expressway toll rates: The Good To Go! toll rate for the first mile of the new expressway is expected to range from $1.20 and $2.40 depending on the time of day.

There will be no HOV exemptions or carpool lanes.

Visit the full SR 509 project page Sign up for project emails

See what's happening

Before the new SR 509 Expressway

Stage 1b: First mile, plus access improvements

Stage 2 opens in 2028: Last two miles, plus access improvements

Completed project includes three miles of new expressway

Get a Good To Go! pass to save $2 on every toll in Washington

With a Good To Go! account, you can choose to Pay As You Go and are only charged after you use a toll road.
To save $2 per toll, you'll need to sign up for a Good To Go! account, get a pass, and install it on your vehicle.
Without a Good To Go! account, you'll pay the higher Pay By Mail rate after receiving a bill in the mail.

Get Good To Go!

Washington State Department of Transportation online open houses