Leland Grove, IL has a population of 1,625 and is the 12,248th largest city in the United States. The population density is 2,601 per sq mi which is 1070% higher than the Illinois average and 2771% higher than the national average. The median age in Leland Grove is 54 which is approximately 45% higher than the Illinois average of 37. In Leland Grove, 73% of the population over 15 years of age are married, 96% speak English and 1% speak Spanish. 68% of Leland Grove residents were born in Illinois, 26% were born out of state, 1% were born outside of the United States and 5% were foreign born.