Monte Alto is a census-designated place (CDP) in Hidalgo County, Texas, United States.

[3] According to the United States Census Bureau, the CDP has a total area of 2.2 square miles (5.7 km2), all land.

[15] As of the census[1] of 2000, there were 1,611 people, 419 households, and 367 families residing in the CDP.

There were 470 housing units at an average density of 209.6 per square mile (80.9/km2).

8.8% of all households were made up of individuals, and 3.1% had someone living alone who was 65 years of age or older.