Round Rock's estimated population is 143,366 as of October 2026, according to an update the city posted October 8.

The figure covers residents within the city limits, rather than everyone with a Round Rock mailing address or the wider metropolitan area.

The city's Planning and Development Services Department calculates population estimates using recent development activity.

Completed single-family housing is reflected in monthly updates, while completed multifamily units enter the estimates quarterly in January, April, July and October.

That schedule matters when comparing monthly releases because different kinds of housing enter the calculation at different intervals.

The estimate is a planning measure, not a new door-to-door census count.

The city also revises its population projections when decennial Census figures become available.

For residents reading growth headlines, the useful first question is what geography and measurement method the number represents.

This release establishes an October snapshot; it does not, by itself, establish a year-over-year growth rate.

Readers who want to compare periods can use the city's demographic information page rather than treating this single total as a trend.

The update was checked October 12, 2026.