Total handle rose from the $8.6m recorded in August to the $38.5m made last month, according to figures released by the Iowa Racing and Gaming Commission.
Internet sports betting made revenue of $2m across the state, 41% of the state’s total.
Prairie Meadows Racetrack and Casino generated revenue of $1.5m, the highest total amount for an individual operator in Iowa.
It also took the highest total in online operations, generating revenue of $1.2m.
Ameristar II took the most from land-based operations, producing revenue of $613,219.
Wild Rose’s three venues are the only operators in the state that are yet to offer sports betting, while several brands are currently unavailable online.
Iowa became the 11th state to legalise sports betting and went live on 15 August. Currently, no state bordering Iowa has regulated sports betting.
While several operators took their first bets in August, September provided a more accurate picture of the potential behind Iowa sports wagering as it saw the start of the college and professional American football seasons and mobile betting apps were launched.
With a tax rate of 7% set on operator’s net receipts, the state took $334,553 for September.
