Plano, IL has a population of 11,929 and is the 3,434th largest city in the United States. The population density is 1,329 per sq mi which is 483% higher than the Illinois average and 1367% higher than the national average. The median age in Plano is 32 which is approximately 14% lower than the Illinois average of 37. In Plano, 54% of the population over 15 years of age are married, 67% speak English and 29% speak Spanish. 69% of Plano residents were born in Illinois, 14% were born out of state, 1% were born outside of the United States and 16% were foreign born.