WSON first signed on ten days after the attack on Pearl Harbor, and has been locally owned for its entire history. For most of its first four decades on the air, WSON was a daytime-only station, signing off at sunset in order to protect CJBC in Toronto. However, a treaty between the United States and Canada signed in the mid-1980s allowed WSON and other daytimers that went off the air to protect Canadian clear-channel stations to begin nighttime operations as well.
In July 2010, owner Henry Lackey, the son of station founder Hecht Lackey, announced that he had agreed to sell WSON to Henson Media, which owns WMSK-AM-FM in Morganfield and Sturgis, Kentucky. The deal received FCC approval and was consummated soon thereafter. 
In September 2011, WSON began simulcasting on an FM translator, W243CU (96.5 FM), which is licensed to Sebree, Kentucky. W243CU, which has an effective radiated power of 250 watts, can be heard up to 30 miles in any direction from its transmitter site in the Wolf Hills north of Henderson.
W243CU allows listeners in Evansville and surrounding communities to listen to WSON's programming after nightfall, when the AM station has to adjust its coverage.