Forest Lake, MN has a population of 19,208 and is the 2,263rd largest city in the United States. The population density is 629 per sq mi which is 917% higher than the Minnesota average and 594% higher than the national average. The median age in Forest Lake is 38 which is approximately equal to the Minnesota average of 38. In Forest Lake, 60% of the population over 15 years of age are married, 94% speak English and 3% speak Spanish. 77% of Forest Lake residents were born in Minnesota, 19% were born out of state, 1% were born outside of the United States and 3% were foreign born.