After a software bug in one of its slot-style games paid enormous jackpots in error, William Hill UK is requesting an unknown number of players to repay what could be a substantial amount of money.

It is believed that a number of Jackpot Drop players received the incorrect rewards, with some claiming on social media that they totaled six figures.

Before the Evoke-owned operator froze their father's account, one Reddit user claimed their father had "won" almost £250,000 (~US$336,000). A screenshot of a friend's account with a frozen balance of £141,897 (~US$190,000) was shared by an X user. Similar instances have been recorded by dozens of social media users, indicating that the mistaken payouts may total millions of pounds.

Holding a cap

On the grounds that the rewards "did not arise from valid gameplay," the operator is now requesting the return of money that was taken out of customers' bank accounts prior to the accounts being frozen.

The Reddit thread claims that William Hill wrote the user's father the following message:

"During a routine review of platform activity, we identified an issue affecting the Jackpot Drop game which resulted in incorrect sums being credited to players’ balances and withdrawals being processed incorrectly.

“As a consequence of this issue, funds were incorrectly credited and, in some cases, withdrawn from several customer accounts, including yours, that were not generated through valid or properly functioning gameplay.”

By nature, random

Jackpot Drop is a progressive slot-style game that "drops" jackpots at random, which could be an issue for William Hill. In contrast, major winnings in a typical progressive are dependent on a particular in-game event, like scoring a top symbol combination or winning a bonus round.

Players may contend that they could not have reasonably understood that an error had happened because Jackpot Drop rewards are supposed to be distributed at random.

According to reports, William Hill is paying clients a payout of about 11% of their withdrew money and requesting the return of the remaining amount. Some players might find that challenging, especially if the funds have already been used for loans or mortgages.

Courts in the UK Turn Toward Players

The courts, who frequently sided with operators since fine print invariably claims that malfunctions nullify all plays and payments, are probably going to take this one. But in recent years, London's High Court has shown itself to be a more player-friendly arena.

The operator claimed the player had been presented a false winning animation due to a technical fault, and the High Court ordered Paddy Power to pay out a £1.1 million (~US$1.4 million) jackpot in March 2026.