Sounder commuter rail

For Seattle's regional light rail system, see Link light rail.

Sounder
A Sounder trainset on the N Line in Edmonds
Overview
Owner	Sound Transit
Locale	Seattle metropolitan area
Transit type	Commuter rail
Number of lines	2
Number of stations	12
Daily ridership	7,827 (2025)
Annual ridership	2,090,709 (2025)
Website	soundtransit.org
Operation
Began operation	September 18, 2000 (2000-09-18)
Operator	BNSF Railway
Reporting marks	SDRX
Number of vehicles	14 locomotives, 78 cars
Train length	2–7 passenger cars
Technical
System length	81.8 miles (131.6 km)
Track gauge	4 ft 8+1⁄2 in (1,435 mm) (standard gauge)
Top speed	79 mph (127 km/h)
System map Map of the central Seattle metropolitan area with Sounder highlighted in black Line Cascades to Vancouver, BC Empire Builder to Chicago Everett Mukilteo Edmonds Snohomish County King County Seattle Tukwila Kent Auburn King County Pierce County Sumner Puyallup Tacoma Dome South Tacoma Lakewood Future extension Future extension Tillicum (2045) DuPont (2045) Cascades to Eugene Coast Starlight to Los Angeles Line All stations are accessible

Sounder (reporting mark SDRX) is a commuter rail system that serves the Seattle metropolitan area in the U.S. state of Washington. Managed by Sound Transit, it uses 82 miles (132 km) of tracks, primarily owned by operator BNSF Railway, and runs with equipment maintained by Amtrak. Sounder is split into two lines that intersect at King Street Station in Seattle: the N Line to Everett and the S Line to Tacoma and Lakewood.

Trains typically operate during peak periods, with morning trips to Seattle and afternoon trips to outlying suburbs. Limited mid-day service is offered on the S Line, and both lines offer special weekend trips for sporting events and other major events. Sounder has 12 stations that connect with Link light rail as well as local and regional bus systems. Most also provide park-and-ride facilities, bicycle lockers, and other amenities. Fares are paid using ORCA cards, paper tickets, and mobile ticketing apps, and validated through proof-of-payment checks. In 2025, the system carried more than 2 million total passengers, or an average of 7,827 on weekdays.

The commuter rail system was preceded by mainline passenger railroad services that began in the late 19th century and two interurban railways that connected Seattle to Everett and Tacoma in the early 20th century. The Municipality of Metropolitan Seattle (now King County Metro) led studies into a modern commuter rail system in the 1980s that were later transferred to the Regional Transit Authority (now Sound Transit), created in 1993. A demonstration service from Everett to Tacoma ran in early 1995, ahead of an unsuccessful ballot measure to fund a regional transit system. A second ballot measure, Sound Move, was passed by voters in November 1996.

Sounder was among the first Sound Transit projects to be launched and construction on its stations began in 1998. The South Line (now the S Line) entered service on September 18, 2000, and was followed by the North Line (now the N Line) on December 26, 2003. Additional trips on both lines were launched in the 2000s after a series of signal and track improvements were completed by Sound Transit and BNSF. The South Line was extended from Tacoma to Lakewood in October 2012 and debuted the first mid-day Sounder trips in 2016. Both lines were rebranded in 2021. An extension of the S Line to DuPont was funded by the Sound Transit 3 package in 2016 and is expected to open in 2045.