Andalusia, IL has a population of 1,148 and is the 14,300th largest city in the United States. The population density is 970 per sq mi which is 336% higher than the Illinois average and 971% higher than the national average. The median age in Andalusia is 43 which is approximately 15% higher than the Illinois average of 37. In Andalusia, 58% of the population over 15 years of age are married, 95% speak English and 3% speak Spanish. 69% of Andalusia residents were born in Illinois, 28% were born out of state, 1% were born outside of the United States and 2% were foreign born.