The Planning and Development Services Department generates monthly population estimates and future population projections based on recent development activity. The population estimate is updated monthly to reflect completed single-family units, and completed multifamily units are added quarterly in January, April, July and October. Projections are adjusted every ten years as decennial Census figures are released.

• As of May 2026, Round Rock’s estimated population is 142,601 (within the city limits). This is also the official annual estimate for 2026.