Arivaca is an unincorporated community in Pima County, Arizona, United States. It is located 11 miles (18 km) north of the Mexican border and 35 miles (56 km) northwest of the port of entry at Nogales. The European-American history of the area dates back at least to 1695, although the community was not founded until 1878. Arivaca has the ZIP code 85601. The 85601 ZIP Code Tabulation Area had a population of 909 at the 2000 census.

Pima County is a county in the south central region of the U.S. state of Arizona. As of the 2020 census, the population was 1,043,433, making it Arizona's second-most populous county. The county seat is Tucson, where most of the population is centered. The county is named after the Pima Native Americans, also known as Tohono O'odham, who are indigenous to this area.