Kilmarnock, VA has a population of 1,440 and is the 12,931st largest city in the United States. The population density is 423 per sq mi which is 121% higher than the Virginia average and 366% higher than the national average. The median age in Kilmarnock is 55 which is approximately 45% higher than the Virginia average of 38. In Kilmarnock, 57% of the population over 15 years of age are married, 98% speak English and 0% speak Spanish. 74% of Kilmarnock residents were born in Virginia, 23% were born out of state, 0% were born outside of the United States and 3% were foreign born.