Of the fastest-growing U.S. counties with a population of 100,000 or more, Hays County took the top spot nationally with 53% growth from 2010-20 according to U.S. census data.
The county grew by 83,960 residents in the decade to 241,067 in 2020.
The data reflects the trend in growth throughout the Austin-San Antonio corridor, with neighboring Comal County growing nearly 49% over the same period, up from 108,472 residents in 2010 to 161,501 in 2020. Austin and San Antonio are two of 14 cities nationally that grew by more than 100,000 residents over the decade.
Of the cities in Hays County along I-35, Buda grew from 7,295 residents in 2010 to 15,108; Kyle grew from 28,016 to 45,697; and San Marcos grew from 44,894 residents in 2010 to 67,553.Hays County bucks a national trend in which 52% of counties saw population decline over the last decade.













