Data and Mapping

Frederick County's 2020 Census Population Estimate was 271,717 Residents

Population estimates are produced for years between decennial censuses and updated annually, with the most recent decennial census used as the base. Frederick County’s estimated July 1, 2021 population was 279,835 residents.

2020 Census Profile (PDF)  |  (.xls)

Quick Facts
QuickFacts provides basic count of population for areas with more than 5,000 people; includes April 1, 2020 population.

2010 Census Profile
County, municipalities, census designated places

2010 U.S. Census Populations

Population Estimates

Population Projections

Building Permits & COO’s by Dwelling Type


Monthly Building Permit Reports  

Frederick County is not responsible for issuing permits in the City of Frederick, and town of Mount Airy. This data is the compiled report of these three entities in regards to number of issued building, housing units, and commercial permits and totals for the cost of construction, impact fees, and excise tax reported on a monthly, year to date, and 5-year average.

Residential Development Pipeline

Includes all county and municipal projects that have received some type of development approval and may or may not be under construction. Development approvals are derived from approved site plan applications, preliminary subdivision plan applications, or a Phase I PUD/MXD applications (county only). 

• Approved Units: Total lots/units that have received either site plan, preliminary subdivision, or Phase I PUD/MXD plan approval
• Developed/Permitted Units: Lots/units that are constructed or have building permits issued
• Available Pipeline: Total remaining lots/units that have not been constructed nor have permits issued
• Recorded Units: Total lots/units that have been recorded and may or may not be developed
• Recorded Units Available: Lots/units that have been recorded but are not developed or have permits issued

Frederick County GIS