Jarrettsville, MD has a population of 3,355 and is the 8,257th largest city in the United States. The population density is 389 per sq mi which is 18% lower than the Maryland average and 329% higher than the national average. The median age in Jarrettsville is 40 which is approximately 5% higher than the Maryland average of 38. In Jarrettsville, 68% of the population over 15 years of age are married, 99% speak English and 0% speak Spanish. 80% of Jarrettsville residents were born in Maryland, 18% were born out of state, 0% were born outside of the United States and 2% were foreign born.