New Madison, OH has a population of 954 and is the 15,442nd largest city in the United States. The population density is 2,326 per sq mi which is 803% higher than the Ohio average and 2467% higher than the national average. The median age in New Madison is 32 which is approximately 18% lower than the Ohio average of 39. In New Madison, 59% of the population over 15 years of age are married, 98% speak English and 1% speak Spanish. 74% of New Madison residents were born in Ohio, 24% were born out of state, 1% were born outside of the United States and 1% were foreign born.