Wagering was up 7.0% month-on-month from $466.7m in November, with the state’s handle split $494.5m for online bets and $4.7m at retail sportsbooks.
Consumers won a total of $454.9m from mobile betting and $4.5m from retail wagering.
As a result, despite this higher spending, gross revenue before free bets fell from $50.2m in November to $38.6m in December.
After accounting for $21.3m worth of free bets – almost all of which were distributed to online players – taxable revenue was $17.3m, down 45.6% month-on-month.
DraftKings led the way in December after taking $146.0m in total bets, followed by Flutter Entertainment-owned FanDuel Group on $128.5m and BetMGM with $103.8m.
In terms of gross revenue, DraftKings also ranked first on $11.0m, ahead of FanDuel with $10.7m and BetMGM on $8.8m.
After taking away free bets, FanDuel was top with $7.2m in revenue, then DraftKings on $6.7m and BetMGM with $1.2m.
Total tax collected from sports betting in December was $1.7m.
The bill allowed players to place bets at tribal casinos and sites that are owned by major league sports teams in the state.