Streamwood, IL has a population of 40,552 and is the 1,019th largest city in the United States. The population density is 5,208 per sq mi which is 2243% higher than the Illinois average and 5649% higher than the national average. The median age in Streamwood is 38 which is approximately 1% higher than the Illinois average of 37. In Streamwood, 58% of the population over 15 years of age are married, 56% speak English and 25% speak Spanish. 60% of Streamwood residents were born in Illinois, 11% were born out of state, 1% were born outside of the United States and 28% were foreign born.