St. Maries, ID has a population of 2,323 and is the 10,210th largest city in the United States. The population density is 1,956 per sq mi which is 10154% higher than the Idaho average and 2059% higher than the national average. The median age in St. Maries is 44 which is approximately 23% higher than the Idaho average of 36. In St. Maries, 59% of the population over 15 years of age are married, 99% speak English and 1% speak Spanish. 45% of St. Maries residents were born in Idaho, 53% were born out of state, 1% were born outside of the United States and 1% were foreign born.