Mason is located in south Illinois. Mason is between the Effingham, Clay county. Mason has 1.29 square miles of land area and 0.00 square miles of water area. As of 2010-2014, the total Mason population is 404, which has grown 2.02% since 2000. The population growth rate is lower than the state average rate of 3.62% and is much lower than the national average rate of 11.61%. Mason median household income is $39,000 in 2010-2014 and has has shrunk by 3.56% since 2000. The income growth rate is much lower than the state average rate of 22.70% and is much lower than the national average rate of 27.36%. Mason median house value is $60,600 in 2010-2014 and has shrunk by -55.38% since 2000. The house value growth rate is much higher than the state average rate of 34.33% and is higher 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 Mason is better than the state average in quality. The Mason area code is 618.