Butler, IL has a population of 154 and is the 25,541st largest city in the United States. The population density is 267 per sq mi which is 20% higher than the Illinois average and 195% higher than the national average. The median age in Butler is 35 which is approximately 6% lower than the Illinois average of 37. In Butler, 75% of the population over 15 years of age are married, 99% speak English and 0% speak Spanish. 91% of Butler residents were born in Illinois, 9% were born out of state, 0% were born outside of the United States and 0% were foreign born.