Ipswich, SD has a population of 992 and is the 15,215th largest city in the United States. The population density is 740 per sq mi which is 6746% higher than the South Dakota average and 717% higher than the national average. The median age in Ipswich is 38 which is approximately 3% higher than the South Dakota average of 37. In Ipswich, 64% of the population over 15 years of age are married, 100% speak English and 0% speak Spanish. 74% of Ipswich residents were born in South Dakota, 26% were born out of state, 0% were born outside of the United States and 1% were foreign born.