TLDR
- Polymarket US must close existing Michigan sports contracts by November 25 under a federal court-approved deal.
- Kalshi, Coinbase and Robinhood have also stopped offering sports contracts in the state.
- Michigan regulators say none of the four platforms holds a state license to take sports wagers.
- Michigan is taking part in Illegal Gambling Awareness Week, which runs November 9 to 13.
- A new free tool, CheckBeforeYouPlay.org, lets users check whether a gambling site is licensed.
Michigan has now stopped four prediction market platforms from offering sports event contracts to its residents. Polymarket US is the latest, and it must close existing contracts held by Michigan users by November 25.
The Michigan Gaming Control Board (MGCB) said none of the four platforms holds a state license to accept sports wagers. The group includes Kalshi, Coinbase, Robinhood and Polymarket US.
How the Four Cases Unfolded
The first major step came in September. The Michigan Department of Attorney General secured a preliminary injunction that bars Kalshi from offering sports event contracts to Michigan residents.
Robinhood then reached an agreement with Michigan regulators to stop offering these contracts. In October, Coinbase agreed to do the same for its Michigan customers, including contracts traded on Kalshi.
On October 28, Polymarket US agreed to stop offering new sports-related event contracts in Michigan. A federal court approved the deal, which also requires the company to close existing Michigan contracts by November 25.
The MGCB is working with the Attorney General’s office to pursue platforms that offer sports event contracts without state approval. The regulator has also sent hundreds of cease-and-desist letters to unlicensed online gambling operators.
“Illegal gambling operators want you to believe they’re just another option. They’re not,” said Henry Williams, executive director of the MGCB.
Williams said players on unlicensed sites have no one checking their age or identity. He added that there is no guarantee winnings will be paid and no regulator to turn to when problems arise.
What Licensed Operators Must Do
Michigan’s licensed online casinos and sportsbooks must confirm that players are at least 21 years old. They must also protect player funds and personal data.
Licensed operators must offer responsible gaming tools, such as deposit and time limits. They must honor the state’s Responsible Gaming Database and give customers a way to file complaints with the MGCB.
Unlicensed operators do not face these rules. The MGCB places offshore gambling sites, sweepstakes casinos and prediction markets offering sports contracts without a Michigan license in this group.
The regulator warned residents about websites that accept only cryptocurrency or promise guaranteed winnings. It also flagged sites that do not verify users’ ages and identities.
Residents can report suspected illegal gambling by calling 1-888-314-2682 or emailing MIGamblingTip@michigan.gov. The Michigan Problem Gambling Helpline, 1-800-GAMBLER, offers free, confidential help 24 hours a day.
The enforcement update comes as Michigan joins Illegal Gambling Awareness Week, which runs November 9 to 13. The International Association of Gaming Regulators (IAGR) organized the event, its first internationally coordinated effort on the issue.
As part of the campaign, IAGR launched CheckBeforeYouPlay.org. The free tool lets users enter a gambling website’s address and check licensing records across participating jurisdictions. Sharp Vision, a regulatory technology company, contributed the tool.
In Michigan, the MGCB is running radio announcements through November with the message “Play it safe. Bet legal.” “Illegal gambling doesn’t stop at state or national borders, and neither can our response,” Williams said.
Under its court-approved agreement, Polymarket US has until November 25 to close all existing sports contracts held by Michigan residents.
