Washington State Route 528

State Route 528
4th Street 64th Street
SR 528 highlighted in red.
Route information
Auxiliary route of I-5
Maintained by WSDOT
Length	3.46 mi[1] (5.57 km)
Existed	1964[2]–present
Major junctions
West end	I-5 in Marysville
Major intersections	SR 529 in Marysville
East end	SR 9 in Marysville
Location
Country	United States
State	Washington
County	Snohomish
Highway system
State highways in Washington Interstate US State Scenic Pre-1964 1964 renumbering Former
← SR 527 → SR 529

State Route 528 (SR 528) is an east–west state highway in Snohomish County, Washington, located entirely within the city of Marysville. It travels 3.5 miles (5.6 km) from an interchange with Interstate 5 (I-5) in downtown Marysville to a junction with SR 9. The four-lane highway uses two local streets—4th Street and 64th Street—and primarily functions as a commuter route to the eastern outskirts of Marysville.

The corridor was added to the state highway system in 1963 as a branch of Primary State Highway 1 (PSH 1). During a highway renumbering the following year, this branch became SR 528; at the time, the highway was not yet complete and was only signed through downtown Marysville. SR 528 was completed in 1988 following the opening of a bridge over Allen Creek; in later years, the entire highway was expanded to four lanes.