Potomac, MD has a population of 45,882 and is the 896th largest city in the United States. The population density is 1,826 per sq mi which is 285% higher than the Maryland average and 1915% higher than the national average. The median age in Potomac is 47 which is approximately 23% higher than the Maryland average of 38. In Potomac, 71% of the population over 15 years of age are married, 67% speak English and 6% speak Spanish. 18% of Potomac residents were born in Maryland, 52% were born out of state, 2% were born outside of the United States and 29% were foreign born.