Nogales, AZ has a population of 20,355 and is the 2,134th largest city in the United States. The population density is 978 per sq mi which is 1601% higher than the Arizona average and 979% higher than the national average. The median age in Nogales is 33 which is approximately 12% lower than the Arizona average of 37. In Nogales, 51% of the population over 15 years of age are married, 12% speak English and 88% speak Spanish. 50% of Nogales residents were born in Arizona, 9% were born out of state, 2% were born outside of the United States and 39% were foreign born.