Area code 202 covers the entirety of the US capital of Washington, DC. It was first put into service on January 01, 1947 and has remained in service since then.
District of Columbia Counties within Area Code 202:
District of Columbia
District of Columbia Major Cities within Area Code 202:
Area Code 202 Time Zone?
Time zone in Washington, DC Eastern Time (GMT-4)
Go here to see the complete list of United States Area Codes.