McAllen is a city located at the southern tip of the U.S. state of Texas within the Rio Grande Valley. Situated directly on the Mexican border, the city limits extend south to the Rio Grande River, positioned across from the Mexican city of Reynosa.
As of the 2025 census estimate, McAllen has a population of 150,640. It is the most populous city in Hidalgo County and ranks as the second most populous city in the Rio Grande Valley. The city serves as an anchor for the McAllen-Edinburg-Mission metropolitan area, which is the fifth largest metropolitan area in Texas.
The broader binational Reynosa–McAllen metropolitan area has a combined population of more than 1.5 million residents. In terms of state rankings, McAllen is currently the 23rd-most populous city in Texas.