The Washington Metropolitan Area Transit Authority (WMATA) is a government agency that runs transit services in the Washington, D.C. metropolitan area. It was created by the US Congress as an interstate compact between Washington, D.C., Maryland, and Virginia. The WMATA is commonly referred to as ‘Metro’.

The WMATA provides rapid transit service under the Metrorail name, fixed-route bus service under the Metrobus brand, and paratransit service under the MetroAccess brand. In 2021, the system had a ridership of 117,605,900, or about 565,700 per weekday as of the second quarter of 2022.

The authority also operates the DC Circulator bus system as part of a public–private partnership. WMATA has its own police force, the Metro Transit Police Department.