Guilford Center, CT has a population of 2,517 and is the 9,804th largest city in the United States. The population density is 1,146 per sq mi which is 77% higher than the Connecticut average and 1165% higher than the national average. The median age in Guilford Center is 54 which is approximately 33% higher than the Connecticut average of 41. In Guilford Center, 47% of the population over 15 years of age are married, 90% speak English and 5% speak Spanish. 47% of Guilford Center residents were born in Connecticut, 42% were born out of state, 2% were born outside of the United States and 8% were foreign born.