Arrowsmith, IL has a population of 267 and is the 23,084th largest city in the United States. The population density is 1,329 per sq mi which is 498% higher than the Illinois average and 1367% higher than the national average. The median age in Arrowsmith is 36 which is approximately 3% lower than the Illinois average of 37. In Arrowsmith, 68% of the population over 15 years of age are married, 93% speak English and 1% speak Spanish. 79% of Arrowsmith residents were born in Illinois, 16% were born out of state, 0% were born outside of the United States and 6% were foreign born.