Spencer is a city in Oklahoma County, Oklahoma, United States, and a part of the Oklahoma City metropolitan area. Its population was 3,978 at the 2020 census, a 1.7% increase from 2010. Established in 1903, the City of Spencer is a historic community located just east of the North Canadian River. Spencer is about 10 miles from downtown Oklahoma City and borders the cities of Nicoma Park to the east and Midwest City to the south.