In the United States, the public and private availability of slot machines is highly regulated by state governments. Nevada is the only state that has no significant restrictions against slot machines both for public and private use. In New Jersey, slot machines are only allowed in casinos operated in Atlantic City. Several states (Illinois, Indiana, Iowa, Louisiana, Mississippi, and Missouri) allow slot machines (as well as any casino-style gambling) only on licensed riverboats or permanent barges. Native American casinos on reservations cannot have true slot machines unless allowed by the state that the tribal casino is located in (per Indian Gaming Act).

Some states have restrictions on the types of slot machines that can be used in a casino or other gaming area. "Class III" slot machines are machines without restrictions, most often seen in Las Vegas or Atlantic City (commonly referred to as "Vegas-style slots"). Some casinos are in states that require them to use "Class II" slot machines, which usually have a player skill requirement attached. The primary difference between a Class III machine and a Type II machine is that with a Class III machine, a player's chance of winning any payout is the same with every play, and each machine operates independently of each other. A Class II machine mimics bingo or scratch-off lottery tickets in that all the machines are linked to play against each other, pulling a predetermined number of winning combinations from a central database and distributing those to all machines.

For a list of state by state regulations on private slot machine ownership, see Slot machine (U.S. state ownership regulations)

Slot clubs
Many American casinos offer free memberships in "slot clubs", which return a small percentage of the amount of money that is bet in the form of "comps" (complimentary food, drinks, hotel rooms, or merchandise), or sometimes as cash back (sometimes with a restriction that the cash be redeemed at a later date). These clubs require that players use a card that is inserted into the slot machine, to allow the casino to track the player's "action" (how much the player bets and for how long), which is often used to establish a level of play that may make a player eligible for additional comps. Comps or cash back from these clubs can make a significant difference in the maximum theoretical return when playing slot machines over a long period of time.