Are Slot Machines Rigged?

Home » Recent Posts » Are Slot Machines Rigged?
Share this on:

Generic slot machine

There is a relative distrust around slot machines that generally infer that casinos can play with them in various ways to make more money and take advantage of players. Here are some examples:

  • “California doesn’t have any minimum payback rules so casinos set slots as low as 60 percent payback.” OR “Since tribal gaming casinos don’t have to report payback, they pay much lower than commercial casinos.”
  • “Casinos will lower payouts on the weekends or holidays to take advantage of more players in the casino.” OR “Casinos will lower payouts on weekdays because there’s less people playing and they need to make that up in the payouts.”
  • “Casinos will RAISE payouts late at night or early in the morning.”
  • “Casinos can ‘Flip the Switch’ and make a section of the casino looser or tighter on a whim.”
  • “If I use my players card the casino will change the paybacks to lower them.”

Are Slot Machines Rigged?

Slot machines are not rigged. While they are designed with a house advantage to over time make money for the casino, the use of randomness to determine the outcome of a spin within a range out possible outcomes ensures that any given spin could be a winning one.

Diving Deeper

As you can see from the questions above, the common thread is that casinos are just trying to wring out every last dollar they can as quickly as possible from players.

All of these things are theoretically possible, but in practice aren’t. Here’s some reasons why.

Casinos Only Have Certain Controls Over Payback

Casinos have some say as to what their slots payback on the casino floor, but not universal say. Slot machines are designed with a set number of payback options. Casinos can pick from them and only them. So in the example of the 60 percent payback, California casinos can’t pay that low because the games aren’t designed to pay that low.

Most slot machines are designed with payback options in a range of 85 to 98 percent. Not all games go all the way down to 85 percent, either, so casinos that want that option will have to simply pass up certain games. 

Older games had an even tighter range, starting at higher payback percentages like 90 or 92 percent, so oftentimes when you see those older machines on the casino floor, it’s entirely possible they’re going to pay more than the modern remade version of that same game because the payback options then and now were different.

Since casinos don’t design the slots, they have to work within the parameters of what they’re offered, and so they can’t just do whatever they want.

The Random Number Generator

Meanwhile, slots use a Random Number Generator, or RNG, to determine the outcome of each spin at the moment a spin is initiated by placing that wager and hitting the spin button. The games do have a set number of possible outcomes – this is how a game maker can ensure that payback percentage over time will align with what is advertised to the casinos. 

But because there are outcomes in that set that can yield a winner, any particular spin can be a winner – even a jackpot handpay! Casinos can’t override the game’s design and have more losing outcomes, or less handpays, than a game is designed to pay out. 

Casinos can choose from six options on a payback screen, give or take. Those are determined by the manufacturers and certified by third-party labs that test the games to ensure they meet what they say they’re going to deliver.

As you can see, there’s a lot of rules that have to be met, and those assertions validated by third parties, just to get a game on the floor. So casinos don’t have unilateral say over these things.

Games Are Designed to Work As Universally As Possible

It’s generally in a slot manufacturer’s best interest to design games that can be approved and sold in as many casino markets as possible. So tribal gaming facilities putting in Class III (Vegas-style) slots are generally buying the same game a casino in Las Vegas or Atlantic City are buying. 

Occasionally there’ll be some differences to meet regulatory requirements, such as what the top payout can be and how hard it is allowed to be to win that top payout. And more often than not, a game will be designed to meet the strictest versions of the requirements so it can be available in as many places as possible.

Casinos Don’t Change Payouts Often, If At All

Many players envision the technical possibility that casinos can be constantly tinkering with payouts behind the scenes. While it makes sense such a thing could exist, it normally doesn’t, for many reasons:

  • The short-term value of upping or lowering payouts is offset in part by the short-term variance. A player could hit a handpay while the game is on its lowest setting, and a second player get quickly drained of cash while on the highest setting – payouts are far from even on any given slot machine.
  • Nevada has strict rules on how and when paybacks can be changed, and many other states follow the lead of Nevada, given its substantial gaming industry and gaming history. Even states where tribal gaming oversight is the norm often have rules about who can open a machine to make these changes and when; some require the gaming regulators to have a representative on sight to observe the changes being made.
  • Because of the amount of effort it can take to update one machine or bank of machines, changes are often done when a game is moved, replaced, or when a specific decision is made about a specific game’s payouts.
  • Most casinos have an overall floor average they are trying to achieve for each denomination’s payback, so most of the time the selected payback will be the one closest to it, whether a bit higher or a bit lower. Rarely do casinos stray farther afield from that, although it certainly can happen.

So the fear that casinos are tinkering with payouts based on a time of day or a holiday weekend is one that’s simply unfounded. Although that said, if you feel that strongly about it, you can always go at another time, as it won’t help or hurt you based on the above.

Players Cards Can’t Impact Payback Either

We’ve seen so many people say that pulling their players card led to a jackpot, or that using a players card changes their payouts. 

Players card systems are primarily designed to collect data, not set data. A players card is effectively a trade off between you and the casino – in exchange for data about our play, you’ll use that data to give us offers that are relevant to our play level and type of play (such as slots vs. table games). 

Players card systems can add free play to a balance, but they can’t change what that machine pays back – that’s in the machine itself, and as discussed earlier is controlled in a very specific manner. Meanwhile, players cards come with a variety of perks, from discounts to earned comps you can spend on property to offers that can get you off to a good start on your next visit.

By not using the card, however, you’re choosing to leave on the table the earned comps and offers that would come from the play recorded when your card is in a machine. So in that way you should nearly always play with a players card to ensure you get credit for that play. Otherwise you’re leaving money on the table.

The only real exception might be if you’re going to play little to nothing relative to your normal casino budget – in those cases skipping the card may be smart to avoid bringing down your daily average. But otherwise, use your card to ensure you get the offers you rightfully have earned.


So are slot machines rigged? We covered a lot of ground here, but it’s a simple question with a complicated answer. Slot machines are not rigged, and there’s a variety of reasons why they’re not. Players may want to have a bogey man they can blame for tough casino sessions, but slots are plenty tough and make oodles of money for the casino – there’s no need for them to work any way but as they’re already designed by slot manufacturers. In the end, it’s all about luck and timing.

Share this on:

19 Replies to “Are Slot Machines Rigged?”

  • Gordon says:

    I like the “Flip the switch”! You’ve already answered some questions I’ve always wondered about.

    • says:

      Aww thanks Gordon! We’re so excited to continue to share some great stuff over the coming weeks and months, and hope you’ll join us for the ride!

  • GuinJ says:

    I’ve seen them physically turn off payouts in banks of machines several times in a casino in Mississippi. A floor lady walked over to a control panel within my eyeshot, keyed in something after giving me and the lady next to me some dirty looks (awe were both playing machines that played music when they hit, and we were both playing TWO machines, as the entire bank was humming). The lady got upset, went over to the machine, keyed something in, and instantly turned off all 4 machines, which had been happily feeding us payoffs for some time before her arrival. It wasn’t a coincidence, as instantly all four machines ceased payoffs. Not one hit again. We continued to play for several more minutes, but arrived separately at the conclusion she had killed them. (We weren’t together, but arrived at the same conclusion). Once more on the same trip the same lady turned off another machine paybacks. Again although it was a separate battery, it was within eyeshot of her little magic monitoring station and I had the displeasure of watching her furiously type in her machine, glancing my direction, as a crowd had gathered because my machine was doing some fantastic bonuses and payouts. She nodded, slammed her little hooded station shut and locked it, then strutted away, and my machine had it’s death throes. So, yes, they still can turn them on and off, at least in Biloxi.

  • Marilyn P says:

    If slot machines have RNGs and each spin is completely independent, how can a casino be guaranteed they will meet their state’s gaming commission rules regarding payout percentages? Either they can change these percentages….or it’s totally random. It can’t be both.

    • says:

      Hi Marilyn! This is a question we actually see a lot, and the answer is pretty simple – the outcome is random within a set of potential outcomes. We wrote this up to dive in deeper:

      • Toby Manning says:

        I have to disagree somewhat on a machine can be flipped or not. I have owned a few machines from casinos, yes actual machines that were in a casino. On those machines that I’ve owned, there was a switch with 3 settings, Easy, Medium and Hard… tried the slots at the different settings and on the easy setting, getting wins and free spins was easy peasy. Now flipping it to hard and I only got the free spins once and hardly hit any line hits.. These were the older style 5x 10x style slot machines..

        • says:

          Hey Toby – we’ve always been upfront that casinos have multiple payback options to work within and that these settings are very much in the control of the casino. But those payback options are inside the machine and the machine has to be opened to change them, which we presume is the case for that switch you’re describing too. This means this isn’t being changed in the middle of a session, which is our point. Some players believe casinos are manipulating payback options in real time and they’re not. If anything, the setting is changed on only rare occasions.

    • Chris says:

      That’s like asking how you can guarantee that blackjack only has a .5% house edge if played perfectly, even when each hand is individual. The answer lies in testing it over many millions of spins, not in observing one or two hands. Program the slot to spin a million times and look at the data. There’s your easy answer.

  • Gordon says:

    Me again, I’m curious if the machines in our (Oregon) local bars are regulated like the ones in casinos? Do they have RNG’s, can the state change the outcomes? It seems like the payouts are less on these machines.
    Thank you all!!

    • says:

      Hi Gordon – the video lottery terminals, if that’s what you’re referring to, are regulated by the Oregon Lottery and have their paybacks incorporated into their pay tables (which offers more information than many slots offer in traditional casinos). They won’t tinker with payouts – they will make enough money just sitting there getting played. Here’s some details from the lottery directly:

  • Russ Orsted says:

    I have seen a growing trend of tying banks of machines together. Same payouts throughout the casino on same game. These machines are now acting as one unit. There may be 15-20 like machines. Different themes, but still the same game. Does this effect the payout %s?

  • CK says:

    On this topic… there are 3 casinos total of which 2 are racinos in the Cleveland Ohio area. Interestingly it seems like certain games pay very differently at the two racinos.

    Sadly for me I have only had ONE hand pay in all my time playing. (mostly Cleveland and the DC area; before that a couple times a year in Atlantic City)

    I would meet my mom and her friends in Atlantic City a couple times a year (ten to 15 years ago) and couple play table games and slots ALL DAY on $200 per day. Now I can lose $200 – with 50 cent to 1.25 bets – in 15 minutes to a half hour.

    Brian, it sure feels like since the Ohio Lottery took over our slots (instead of a “gaming commission” that it is more like the lottery. Meaning Win Big or Win NOTHING (no play back). Is that possible?

    • says:

      Hi CK – oftentimes people think that this change or that around ownership or payouts or whatnot is happening, but in fact other changes are happening that make our money not last as long as it used to. We wrote this post to talk about it because there are other things at play that make money go quicker than it did 15 years ago. Today’s games are designed to often win bigger, or don’t win at all, moreso than older games, for instance. Check it out here:

  • Dana says:

    I’ve always wondered ‘how’ they change payouts on slot machines. Do they have to do it by hand, each machine? Do they just have a switch for same kind of machines or blocks of machines?

    • says:

      The most traditional way on a modern slot machine is to open the machine and update the settings. Some machines require a different chip, usually older ones. Think of it as similar to going into your cell phone and making changes to those settings. But the biggest difference is when you change the settings, they have to document it in many jurisdictions, and the machine will do a self-check and restart after any internal settings changes, which can take a few minutes.

  • Jo says:

    There’s one more (big) advantage to using your card while playing that you didn’t mention. Casinos use the in/out info from your card to generate win/loss reports at the end of the year. So if you want to claim a deduction for gambling losses on your taxes, you need to use your card!

Leave a Comment

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Play Online Casinos

Sign Up with BetMGM Casino and get a Deposit Match up to $1,000, plus $25 in Site Credits on the house! Available in MI, NJ, PA & WV. US promotional offers not valid in Ontario.

Use code SWITCH2500 for a 100% deposit match up to $2,500, and 2,500 Reward Credits, with $25+ in wagers placed (MI, NJ, PA & WV).

New sign-ups with DraftKings Casino in MI, NJ, PA & WV will receive $35 Casino Credits, plus Play $5 and Get $50 Back in Casino Credits Instantly!

Sign Up and deposit $10+ at FanDuel to get a Welcome Offer of a $20 Bonus + Up to $1,000 Play it Again based on your net losses in the first 24 hours in MI, NJ, PA & WV!

Play Social Casinos

Ready to give Show Me Vegas Slots a try? Get 10 million coins to play Show Me Vegas Slots with promo code SWITCH!

New players to 88 Fortunes Slots receive 5 billion coins as a thank you for signing up!

Sign Up and get a Welcome Bonus of 2,000,000 FREE Gold Coins & 2 FREE Sweeps Coins. Get started today!

Sign Up for LuckyLand Slots and get a Welcome Bonus of 7,777 FREE Gold Coins & 10 FREE Sweeps Coins!

Online Game Spotlight
Double Patriot

Classic Everi Three-Reel Slot with a Fresh Twist

Play Online Sportsbooks

Sign Up to get a Bet $5, Get $150 in Bonus Bets if your bet wins!

Use code SWITCH1000 to get your first bet back in Bonus Bets, up to $1,000, if you lose.

​SIGN UP to get $150 instantly in Bonus Bets* (NC, $5+ bet required) or up to $1500 in Bonus Bets* Back if Your First Bet Doesn't Win (All Other Eligible States)!

New Players get a $1,500 No Sweat Bet, a $50 Bonus Bet with $5 deposit, & Get a No Sweat NBA SGP Every Day of NBA Playoffs! New players outside MA also get 20% Match up to $1,000 (25x PTR).

Social Game Spotlight
Kronos Unleashed Slot

Frequent Feature Livens Up Super Tall Reels

Dragons vs. Pandas Slot Machine

Two Sets of Reels Battle it Out