Penfield, IL has a population of 151 and is the 25,631st largest city in the United States. The population density is 587 per sq mi which is 164% higher than the Illinois average and 548% higher than the national average. The median age in Penfield is 47 which is approximately 26% higher than the Illinois average of 37. In Penfield, 65% of the population over 15 years of age are married, 85% speak English and 13% speak Spanish. 67% of Penfield residents were born in Illinois, 26% were born out of state, 5% were born outside of the United States and 2% were foreign born.