County facts · Population growth · October 23, 2026

Fastest Growing Counties in the US, 2020 to 2025

The fastest growing US counties from April 2020 to July 2025 by percent and by people added, from Census estimates, with each official parcel map.

Looking for the fastest growing counties in the US? Using the Census Bureau's Vintage 2025 estimates, the fastest growing county by percentage from April 2020 to July 2025 was Kaufman County, Texas (+44.0%), and the county that added the most people was Harris County, Texas (+314,618). Over the same period the country as a whole went from about 331,516,113 to 341,784,857 residents (+3.1%).

1,845 of the 3,144 counties and county equivalents grew. The tables below rank them by percent, by people added, and over the most recent year, with a link to each county's official parcel map.

The 25 fastest growing US counties by percent, 2020 to 2025

Among the 50 fastest by percent, the states that show up most are Texas (19), Florida (10), Georgia (5) and South Carolina (4).

The 25 counties that added the most people

Together these 25 added about 3,484,301 residents.

Fastest growing among counties with 100,000+ residents

Small counties can post big percentages on a modest number of newcomers. Limiting the list to counties with at least 100,000 residents in July 2025:

The last year alone: July 2024 to July 2025

One-year swings in very small counties can come from a handful of people, so this list covers counties with at least 10,000 residents in July 2024.

1. Jasper County, South Carolina: +6.0% (+2,195)
2. Waller County, Texas: +5.7% (+3,761)
3. Kaufman County, Texas: +5.7% (+11,225)
4. Jackson County, Georgia: +5.3% (+4,963)
5. Long County, Georgia: +5.2% (+1,064)
6. Brunswick County, North Carolina: +4.7% (+7,813)
7. Pinal County, Arizona: +4.6% (+23,654)
8. Liberty County, Texas: +4.4% (+5,073)
9. Dawson County, Georgia: +4.2% (+1,420)
10. Caldwell County, Texas: +4.2% (+2,211)

Growth by state

How many counties in each state grew between April 2020 and July 2025. State names link to our fastest-growing-counties guide where we have one, otherwise to the state's county list.

The District of Columbia is a single county equivalent and is left out of the state table. Connecticut appears by planning region: since 2022 the Census Bureau uses its 9 planning regions instead of its 8 historic counties, and Platbookmapper's county pages still follow the historic counties, so those rows have no parcel-viewer link.

What growth looks like on a parcel map

• New lots show up as plats first. When land is subdivided, the plat is recorded with the county and the parcel layer catches up on its own schedule, so a brand-new lot may not appear on the map for a while. Check the recorder's recent plats if a parcel looks missing.
• Parcel numbers change after splits. A tract that was one parcel last year can be several today. Search by owner name or address as well as by an old parcel number.
• City limits move. Growing cities annex land, which changes who handles zoning and permits even though the county still keeps the deed and the tax map.
• Percent is not the same as people. A small county can post a big percentage on a modest number of new residents, so read the people-added column too.

Related guides

• US counties losing population
• Fastest growing counties in Texas
• Fastest growing counties in Florida
• Fastest growing counties in Georgia
• Fastest growing counties in North Carolina
• Fastest growing counties in South Carolina
• Fastest growing counties in Tennessee
• Fastest growing counties in Alabama
• Fastest growing counties in Virginia
• Most populous counties in the US

Sources

• U.S. Census Bureau, Population Estimates Program, county totals, Vintage 2025 (April 1, 2020 estimates base and July 1, 2020–2025 estimates, with components of change). 50 states and the District of Columbia; Puerto Rico's municipios are not included.
• Platbookmapper county GIS directory (live data file behind our county pages, pulled October 23, 2026) for each official parcel viewer.