Burlington, NJ has a population of 9,850 and is the 3,978th largest city in the United States. The population density is 3,216 per sq mi which is 321529% higher than the New Jersey average and 3450% higher than the national average. The median age in Burlington is 41 which is approximately 4% higher than the New Jersey average of 40. In Burlington, 52% of the population over 15 years of age are married, 84% speak English and 5% speak Spanish. 64% of Burlington residents were born in New Jersey, 24% were born out of state, 2% were born outside of the United States and 10% were foreign born.