Petersburg, VA has a population of 31,997 and is the 1,332nd largest city in the United States. The population density is 1,409 per sq mi which is 636% higher than the Virginia average and 1455% higher than the national average. The median age in Petersburg is 39 which is approximately 3% higher than the Virginia average of 38. In Petersburg, 41% of the population over 15 years of age are married, 93% speak English and 5% speak Spanish. 71% of Petersburg residents were born in Virginia, 24% were born out of state, 2% were born outside of the United States and 3% were foreign born.