Upperco (formerly known as Arcadia) is an unincorporated community in Baltimore and Carroll counties, Maryland, United States.

[2] The population as of the 2000 census for zip code 21155, part of which covers Upperco, was 2349.

[3] It is adjacent to Maryland Route 30, between the much larger towns of Reistertown and Hampstead.

The community's fairground is home to several annual public events, such as shows held by the Maryland Steam Historical Society—featuring steam engines, antique cars, tractor pulls, and a flea market—and fundraising events for the local volunteer fire company, including a demolition derby, bluegrass music festival, and yuletide village.

broke ground on the new facility in July 2021, with a budget of $8 million.