Collin County growth surges as four cities rank among nation's fastest

Collin County’s population climbed to 1,297,179, a gain of 42,966 residents in just one year that left the county growing faster than nearly anywhere else in the country by sheer numbers. The surge put Collin County at 3.4% annual growth and second nationally for numeric gain, behind Harris County in the Houston area.

The growth was not spread evenly. Celina led the nation with a 24.6% jump, adding more than 12,700 people in a single year. Princeton ranked third among U.S. cities with populations above 20,000, Melissa ranked fourth and Anna ranked fifth, making four of the top five fastest-growing cities in North Texas. McKinney also kept expanding, placing tenth nationally for numeric growth after adding more than 8,500 residents.

The new Census estimates put hard numbers behind what many families already see on daily commutes and in neighborhood construction. Princeton’s population reached 43,524, while Melissa rose to 29,969. McKinney’s city website lists 237,130 residents as of Jan. 1, 2026, underscoring how quickly the county’s largest city has moved further into big-suburban territory.

That kind of growth carries real costs. More residents mean more pressure on roads, school campuses, water and sewer service, police and fire coverage, and the supply of homes people can actually afford. In Collin County, the expansion has been concentrated in the same corridors where congestion, school crowding and land development are already changing daily routines.

County and regional planners have been preparing for that strain for years. Collin County’s Mobility Plan Update, finalized in August 2014, was designed to identify and coordinate transportation needs for a growing population. The North Central Texas Council of Governments says its Collin County Strategic Roadway Plan is helping identify major transportation needs to improve mobility and support future growth east of U.S. 75.

The housing numbers show why the pressure has not eased. Collin County had an estimated 471,426 housing units in 2024, along with 18,813 building permits, evidence that construction is still racing to keep up. A recent countywide analysis said Collin County was nearing 1.273 million residents in Texas Demographic Center projections, suggesting the county’s population boom is not a one-year spike but a sustained shift that keeps pushing infrastructure, affordability and land use to the center of local decision-making.