May marked the fourth consecutive month of advertising revenue growth for the radio market which is up 8.2% to May 2012.
The industry generated $65.697m in ad revenue last month, according to figures released by Commercial Radio Australia (CRA), with the charge lead by Sydney.
Sydney recorded the most growth of 13.4% to $21.743m with Melbourne in second place with an increase of 8.77% year-on-year to $19.589m.
Adelaide was the only market to drop, sliding 4.3% to $5.977m, as Brisbane and Perth grew by 7.89% to $10.19m and 4.49% to $8.197m respectively.
The financial year to end of May shows total growth of 0.26% to revenue of $622.031m for the five metro markets.