Eight of the top 10 counties in the U.S. with the largest annual numeric growth in population are in Texas, including top-ranked Harris County that grew from 4,731,122 April 1, 2020, to 4,781,337 July 1, 2022, and 4,835,125 July 1, 2023. Data from U.S. Census Bureau show Texas’ Collin County is second with 1,195,359 July 1, 2023 (after 1,066,467 July 1, 2020), and the state’s Montgomery County is third with 711,354 July 1, 2023 (after 620,460 July 1, 2020).
Maricopa County in Arizona is fourth, and Polk County in Florida is fifth. Also from Texas in the top 10 are 6-Denton County, 7-Fort Bend, 8-Bexar, 9-Tarrant and 10-Williamson.