Slots and fraud online is a well-documented issue where most of the commonly reported behaviors include refusal to pay withdrawals or cheating software with rigged payouts. An online casino with multiple confirmed cases of fraudulent behavior is often called a rogue by the online casino player community. Several cases have been reported where a casino refuses to pay withdrawals promptly. A rogue casino may intentionally delay a withdrawal hoping that the player will continue gambling with the money in the account and then lose it all back to them. Other rogue online casinos attempt to refuse paying their customers by retroactively applying unfair slots terms to their house rules, or omitting information in their rules guidelines.
Cheating software appears to be less common than payout problems where the operator adjusts an older brand of the software. There are some casinos, which have been identified as giving high winning probability when players are wagering on the games within in a web version and play slots in fun mode, comparing to playing for real money. Others use spamming techniques excessively in order to promote themselves. Attempts have been made to self regulate where casino gaming portals and player forums have been maintaining blacklists of rogue casinos. While some carry more authority than others do, most of the blacklists constitute just individual webmaster and player opinions rather than anything official from any type of a regulating body to stop online slots fraud.