Las Cruces is a city in Doña Ana County, New Mexico, United States, and its county seat. The population was 111,385 at the 2020 census, making it the second-most populous city in New Mexico, and the largest in both Doña Ana County and southern New Mexico. It is the principal city of the Las Cruces metropolitan statistical area, which encompasses all of Doña Ana County and had an estimated 230,000 residents in 2024. The city is also part of the larger El Paso–Las Cruces combined statistical area.