Hillsboro, TX has a population of 8,358 and is the 4,546th largest city in the United States. The population density is 769 per sq mi which is 693% higher than the Texas average and 749% higher than the national average. The median age in Hillsboro is 32 which is approximately 7% lower than the Texas average of 34. In Hillsboro, 50% of the population over 15 years of age are married, 64% speak English and 34% speak Spanish. 67% of Hillsboro residents were born in Texas, 15% were born out of state, 0% were born outside of the United States and 18% were foreign born.