Currently operating commuter rail systems in the United States

CT Rail, stylized as CTrail, is the brand for commuter rail services overseen by the Connecticut Department of Transportation (CTDOT), in the U.S. state of Connecticut, with services on the Hartford Line extending into Massachusetts. CTDOT oversees two lines: Shore Line East, between New Haven and New London, Connecticut, and the Hartford Line, from New Haven, through Hartford, to Springfield, Massachusetts.

The WeGo Star (reporting mark NRTX), formerly the Music City Star, is a commuter rail service running between Nashville and Lebanon, Tennessee. The service uses the existing track of the Nashville and Eastern Railroad. The line stops at seven stations: Riverfront (Nashville), Donelson, Hermitage, Mt. Juliet, Martha, Hamilton Springs and Lebanon. The operation covers 32 miles (51 km) of rail line. Service began on September 18, 2006. In 2024, the line had a ridership of 125,900.

The Blue Line is a planned light rail line for connecting Austin–Bergstrom International Airport with downtown Austin, Texas. It is still in the planning stages as a part of CapMetro's Project Connect. It is estimated to begin revenue service as early as 2029.

The A-train is a hybrid rail service in Denton County, Texas, United States. The service is operated by Rio Grande Pacific under the authority of the Denton County Transportation Authority (DCTA).

TEXRail is a hybrid rail line (i.e., a non-commuter rail service that operates on the national rail network) in Tarrant County, Texas that provides service between downtown Fort Worth and Dallas/Fort Worth International Airport, with intermediate stations in North Richland Hills and Grapevine. It is operated by Trinity Metro (formerly Fort Worth Transportation Authority). The line was opened for preview service on December 31, 2018 and started revenue service on January 10, 2019. In 2024, the system had a ridership of 809,300, or about 2,700 per weekday.

The Hartford Line is a commuter rail service between New Haven, Connecticut, and Springfield, Massachusetts, using the Amtrak-owned New Haven–Springfield Line. The project is a joint venture between the states of Connecticut and Massachusetts, with support from the federal government as well. CT Rail-branded trains provide service along the corridor, and riders can use Hartford Line tickets to travel on board most Amtrak trains along the corridor at the same prices. The service launched on June 16, 2018.

eBART (East Contra Costa County BART extension) is a hybrid rail (light rail with some features similar to commuter rail) branch line of the Bay Area Rapid Transit (BART) system in eastern Contra Costa County, California, United States. The line extends the Yellow Line beyond Pittsburg/Bay Point station to Antioch station.

The A Line (formerly the University of Colorado A Line for sponsorship reasons) is a Regional Transportation District (RTD) commuter rail line serving Denver and Aurora, Colorado, operating between downtown Denver and Denver International Airport (DIA). During planning and construction, it was also known as the East Rail Line, but most locals refer to it as the A Line. Despite its former title, the line does not serve the campuses of the University of Colorado.

The Hartford Line is a commuter rail service between New Haven, Connecticut, and Springfield, Massachusetts, using the Amtrak-owned New Haven–Springfield Line. The project is a joint venture between the states of Connecticut and Massachusetts, with support from the federal government as well. CT Rail-branded trains provide service along the corridor, and riders can use Hartford Line tickets to travel on board most Amtrak trains along the corridor at the same prices. The service launched on June 16, 2018.

Sounder (reporting mark SDRX) is a commuter rail system that serves the Seattle metropolitan area in the U.S. state of Washington. It is managed by Sound Transit and operated by BNSF Railway on 82 miles (132 km) of tracks, primarily owned by BNSF, using 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.