Milroy, PA has a population of 1,524 and is the 12,593rd largest city in the United States. The population density is 1,510 per sq mi which is 445% higher than the Pennsylvania average and 1567% higher than the national average. The median age in Milroy is 44 which is approximately 8% higher than the Pennsylvania average of 41. In Milroy, 63% of the population over 15 years of age are married, 96% speak English and 0% speak Spanish. 89% of Milroy residents were born in Pennsylvania, 8% were born out of state, 0% were born outside of the United States and 3% were foreign born.