Madison, IL has a population of 3,825 and is the 7,646th largest city in the United States. The population density is 263 per sq mi which is 18% higher than the Illinois average and 191% higher than the national average. The median age in Madison is 35 which is approximately 6% lower than the Illinois average of 37. In Madison, 33% of the population over 15 years of age are married, 99% speak English and 0% speak Spanish. 67% of Madison residents were born in Illinois, 31% were born out of state, 0% were born outside of the United States and 1% were foreign born.