Union is located in north Kentucky. Union is part of Boone County. Union has 3.33 square miles of land area and has no water area. As of 2010-2014, the total Union population is 5,569, which has grown 92.50% since 2000. The population growth rate is much higher than the state average rate of 8.45% and is much higher than the national average rate of 11.61%. Union median household income is $103,929 in 2010-2014 and has grown by 21.62% since 2000. The income growth rate is lower than the state average rate of 28.72% and is lower than the national average rate of 27.36%. Union median house value is $236,000 in 2010-2014 and has grown by 25.80% since 2000. The house value growth rate is much lower than the state average rate of 40.25% and is much lower than the national average rate of 46.91%. As a reference, the national Consumer Price Index (CPI) inflation rate for the same period is 26.63%. On average, the public school district that covers Union is much better than the state average in quality. The Union area code is 859.