Ask the Wizard: Slots - Payback Percentages
Is there a particular time of the day or night that’s better to play [slots] and a time that’s best to avoid?
— Mary from San Gabriel, California
No, any given machine pays equally at all times.
Which are the best slots to play and is it better to play 3 coins all the time or rotate from 2-3 coins.
— Gary from Geulph, Canada
Most slot machiens offer an incentive to play the maximum coins. For example 2 coins may pay 2000 on the jackpot but 3 coins will pay 5000. On a jackpot per coin basis maximum coins is usually the best bet. So if there a maximum coin incentive then it is better to always play the maximum coins. I’m afraid I can’t answer the question on which slot machines are the best to play, the casinos don’t usually tell you what their payback percent is for any given machine.
I recently went to the Couer d’ Alene Tribal Casino in Worley, Idaho. It was late at night and they were retrieving money from the video slot machines. When they shut down the machines, a screen pops up with all kinds of information regarding coins in, coins paid, etc. I noticed that the "hit rate" was set to 37% on the bank of machines that I was playing. This seems really low! Not knowing exactly what I was seeing, I thought best to ask the Wizard!
— Dirks from Spokane, Washington
Interesting question. I’m sure that didn’t refer to the payback percentage, it would be way too low. It may be the percentage of hands that the player wins anything. However with perfect strategy the player will win something about 45% of the time on a jacks or better machine. Other versions of video poker are not far from that 45%. Can anyone else help with this one?
Do casinos have the right to change minor prize odds on multi-casino progressive linked games such as megabucks or wheel of fortune or are the odds set the same for all casinos. The prizes I’m refering to are the bar, double bar Tripple bar hits. Also do the video poker games such as triply play poker the same odds for all casinos or does each casino have the right to vary their own odds for the game.
— James from Cherry Hill
In general the casino can choose their own payback percentages from the manufacturer. They are still confined to certain minimums determined by the gaming authorities but most are well above those limits anyway. I speculate that there is no exception for linked progressive machines on the smaller prizes but that the probability on the jackpot may be constant. The odds on video poker can be calculated based on the payoff table which vary from place to place.
I know this will be almost impossible for you to figure out, but I’m curious to know approximately how many people play Cash Splash on a daily basis and some idea of the odds against me. I am especially curious to know if online progressive slots offer better chances of hitting that jackpot than land-based progressives.
— Donna from Los Angeles, California
You’re right, it is impossible for me to know without Microgaming giving me the details on how their reels are weighted. I have asked some of the major software companies for such information but thus far nobody has volunteered anything. However I can tell you that the average payback for all slots at the Golden Palace for the month of March 2000 was 95.67%. This information is available at the
Golden Palace web site, click on the Price Waterhouse Coopers monthly payout review.
Concerning the Cash Splash progressive slot game played on Microgaming sites... Is the jackpot paid by all participating casinos? If so, does each casino have the same payout percentage set for these machines or is it set by each casino individually? What about mid level payouts on these Cash Splash machines? Thank you very much.
— Helen from Memphis, U.S.
I would assume that the odds are the same at all Microgaming casinos. All casinos probably contribute money to the same account from which the jackpot is paid. This way the individual casino from which the jackpot was hit does not have to reach into their own pocket when somebody wins. Mid level payouts are probably paid by the casino itself.
When a local gaming authority sets a minimum payout for slots does that minimum apply to each individual machine or a casino average payout? I know some games are set from the manufacturer higher than other and some lower. For example if the minimum is lets say 87% can one machine be set to 60% and another set to 120% for and average of 90% thus exceeding the minimum or does each machine must pay atlease 87%.
— Jim from U.S.
The minimum applies to every machine. Someone with the Gaming Control Board in Carson City, Nevada, told me that every machine in the state must meet minimum payback percentages. The only exception, he said, are on some antique machines in Virginia City.
Lets say you have a slot machine like sizzling seven’s that pays a top prize of 60 coins for one coin played 500 for 2 coins and the progressive for the 3rd coin. Let’s say the machine is played only by one coin players receiving only 60 coins max prize. In other words they excluded themselves from the progressive and 500 coin hits. How does a manufacturer program the machine to satisfy local gaming regulations if this machine will never pay out a jackpot higher than 60 coins. Obviously the machine doesn’t return the same amount to one coin players as it does for three coin players. Doesn’t this violate the minimum payout requirement or does the machine compensate for this?
— Jim from USA
I’m not sure but I think that for purposes of meeting minimum return requirements the gaming authorities assume that the players are playing optimal strategy. In the case of slots this would mean the player is playing the maximum coins for the maximum return. However I think the return is only about 1% less if the player does not play the maximum coins. Due to the competitive nature of most gambling jurisdictions the slots pay out much more than 1% above the minimum requirements.
Are Indian Casinos held to the same standards as non-Indian? Is the pay out regulated as overall per month or regulated per machine? If payout is overall, couldn’t a casino adjust payouts for any machine at any time of day or week? 3. When walking into one of these "Indian" casinos, I can stand for 5 min, listen to the bells and tunes, and know if it will be a good day. Take 300 slot machines with fixed payouts and listen, given the same number of players should produce the same frequency of sounds. It doesn’t. I think all of the new machines are networked and changed based on overall psychological factors of gamers.
— K Foster from Temecula, California
In general Indian casinos are either self-regulated or not regulated at all. Don’t assume any kind of minimum return on the slot machines. Changing the overall return on the slots would require opening each machine and changing the e-prom chips. This could be done overnight I suppose but I don’t think they would be this devious. Your sound level hypothesis sounds interesting but I would need more information on decibel levels, number of players, and playing speed before I am convinced the difference isn’t due to chance, different playing speed, standing in a different part of the casino, or incorrectly estimating the number of players.
How is it possible for casinos to program their slot machines to pay out a regulated percentage if the slot machines run off a random number generator? It would seem there is no way to know what number or combination (winning or losing) is next.
— Steve from Milton, U.S.
The casinos don’t actually program the casinos to pay a certain percentage but determine the weighting of the reels so that the theoretical return is whatever they wish. In the short run the actual return can be either much higher or lower than the theoretical return. However the laws of mathematics dictate that the actual return will get closer to the theoretical return the greater the number of trials.
I’ve noticed some new video slot machines (Money to burn, High Bid, Money for nothing, Who Dun it, etc) that differ from the normal 3 reel slots in the following ways - first they have 5 reels. You can typically bet on 1 to 9 paylines (even though some have as many as 15 different pay lines), and multiple coins per line; thus, with 9 pay lines and 5 coins played per line, you would have a total bet of 45 coins (even in nickles, this can start to add up!). Most payoffs are multiples of the line bet, even though there are some "bonus" wins that pay multiples of the total amount bet. My question is - Is it best to always pay all possible pay lines, or is there an optimum combination of pay lines to play to achieve the best return. I suspect that getting a winning combination on any particular pay line is the same for all, but wondered if you have any better insight to share.
— Scott from Leawood, USA
I believe each frame in these video slots are weighted the same way. Assuming this to be true any given line is equally likely to produce any given combination. Thus the return is the same regardless of the number of coins played. However I am not sure of this, slot makers are notoriously secretive about such things.
I looked over your expected payouts for the various deuces wild pay schedules, but I did not find the particular schedule I was looking for. Could you tell me the expected payout for a deuces wild with the following schedule:
Royal flush - 840
Four deuces - 200
Wild Royal - 20
Five of a kind - 12
Straight flush - 9
Four of a kind - 5
Full house - 3
Flush - 2
Straight - 2
Three of a kind - 1
I would do this myself, but I am unable to use the necessary software, as I am not a windows user.
— Ben from Henderson, Nevada
Do casinos have the ability to change the slot payout percent (or really take percentage) at any time after receiving the machine? I always thought that was set at the manufacturer and that the RNG was not changeable.
— Jarin from San Diego, CA
Physically all you have to do to change the return of the slot machine is change the EPROM chip inside. Assuming the casino manager had all the EPROM chips, which I think they sometimes do, they could make the change themselves. However in a major jurisdiction the change would have to be reported to the gaming authorities, not to mention internal paperwork. The random number generator is constant, it is what the program does with the random numbers that determines the return.
Do the five ten and twenty-five dollar machines pay off just a little better i seem to have a little better luck on them rather than the quarter machines which seem to swallow up a twenty fast?
— Mario from Troy, New York
In general the higher the coinage the better the rate of return is. However in my own research I have seen plenty of exceptions, notably dollar machines that paid less than quarters.
Did old slot machines, that were not computer operated have greater chances of winning? If so, how did they work?
— Sarah from Oshawa, Ontario, Canada
I don’t know whether the chances of winning were better or not. They worked the same way as they do now except each stop on each reel had an equal chance. The very early ones didn’t pay money but chewing gum, which explains the bar symbols (sticks of gum) and fruits (flavors) on some modern slot machines.
Have you calculated any of the odds for the slot machines at Harrah’s Cherokee Casino? NC law requires games of skill. As a result of this law all of the common slots such as Double Diamond, Red-White-Blue, etc were installed with a two spin option. After the first spin you may hold or respin any of the three rows to obtain final results. Charts are available on every machine to show the total number of each symbol and blanks in each row. Since these machines are IGT machines I assume that the symbols are weighted and randomly selected as posted. If this is true then the payback % can be calculated just as it is in video poker. Just curious if you had any info.
— David from Peachland, North Carolina
I’ve been asked about these North Carolina slot machines so many times I’m tempted to fly there just to see them for myself. Yes, if they did give the probability of each symbol for each reel then an optimal strategy and a return could be fairly easily calculated. However I have never actually seen such a table and have never worked out the odds.
To begin, I am not a mathematician but I am a casino player. I have followed some of your articles in Casino Player magazine and I subscribe to your on-line newsletter. By the way, I hope you had a wonderful time with your family and friends in Seattle.
I just had an eye-opening experience at Casino Windsor. No where do they publish their percent payback on slots. However, that aside, I was going to play quarter (my comfort level) video poker. I was really taken aback when I put up the paytable. They were 5/4 machines. I am talking Jacks or better was only 5 coins on a full house and 4 coins on a flush. I looked at about 20 machines and only found one that paid any better and that was a 6/4 machine.
As I stated, I am not a mathematician but I think that payback percentage must be in the very low 70s. Needless to say I didn’t play video poker there because I know that the longer I would have played the greater the loss I could have expected with the house taking approximately $30.00 from every $100.00 put through the machine. That is not a gamble with some expectation of winning, it is a sure loss for players. On the Detroit side of the river, MGM Grand has their machines at 7/5. Not really great but a whole lot better than 5/4.
Could you please tell me the exact percentage payback on the 5/4 and 7/5 machines. Since none of the area casinos post their average payback on slots I am (and this is dangerous) assuming that their reel slots payback the same percentages. Best regards.
— Mort from Walled Lake, Michigan
Actually with perfect play the 5/4 pay table return 92.78%. Still one of the worst pay tables I have ever heard of. Have you tried the Greektown casino in Detroit? I don’t know what games they have but I do know they have had security remove several winning video poker players from the building, including a old lady who hit a royal on a machine with a 97% pay table. They must have something good enough to warrant throwing winners out for. Here is an article for more information:
www.freep.com/news/metro/dicker27_20021127.htm
How does the RNG logic interact with the "hold %"? I believe that most machine are set to hold X% and that over time that number will be reached. It would seem that that "hold" number must have some influence on the odds a machine will pay or not. I realize that a newly installed machine that has never been played can hit the royal on the first play, however, it is my belief that over time, the hold % will met by that machine. I have also heard the term "cycle". I slot tech at a casino told me that a machine was on a 365-day cycle. What does that mean?
— Anonymous
First lets clear up what the term "hold" means. For purposes of electronic games it is the theoretical return the game is set to. In both video poker and slots each play is random and independent of all past plays. The laws of mathematics dictate that even with independent trials the as the sample size gets larger the actual return will tend to get closer to the theoretical mean, or the hold. So contrary to popular belief a machine never goes hot or cold to get back in balance. Never mind the term "cycle." It is a poorly named industry term for the number of possible outcomes of the random number generators inside the machine. Unfortunately the term has trickled down only to confuse low level employees and players alike. Contrary to popular myth there are no cycles and again each play is equally random and independent of all other plays.
How often does a casino change the percentage on a slot machine?
— Nathan from Marquette, Michigan
Not often. Contrary to popular myth the casinos don’t tighten the machines on weekends or whenever it is busy. Here in Las Vegas the casinos have to fill out a form every time they change the percentage on each game. Most slot managers I have spoken with have a policy on what coinage is set to what return. I tend to think the most likely reason to change the percentage would a change in ownership and/or management, which do not happen often.
Very simple question on the online gaming side. Casino states that their RNG gives back for example 96.7. We’re all aware that payment companies charge them as a merchant, let’s say an industry avg. 3.5% transaction fee on the drop (not on the take). So where is the operator making all their money or are the RNG’s all playing with us?
— Josh from Stamford
The 96.7% applies to total money bet and transaction fees generally only apply to deposits and/or withdrawals. Players generally circulate through the same money and thus bet much more than they deposit. As I discussed in the September 18, 2005, column a player could bet through about 1.5 million dollars with a $10,000 bankroll and betting $5 at a time in blackjack. In this case the casino would make their profit based on 1.5 million in bets but pay expenses based only on $10,000.
Wizard, what do you think about the new "server based" slot machines currently being tested at Barona Valley Ranch? Apparently this technology allows the casino to instantly change the machines from their back offices - including the games offered, denominations, and.....the payouts! I think this is going a bit far. I mean what’s to stop the house from targeting certain players (like the drunk high roller) and making it tougher for that player to win? We all know the casinos can pretty much keep an eye on any player they want any time. Between the surveillance and now this technology it seems to give the house too much of an edge. Suppose a table player has a heated disagreement with a dealer or pit boss over a hand (which occasionally happens); now this same player goes to the slots and the house can extract revenge by making his machine pay out less??!! Of course they could "favor" certain players too...which could be just as dangerous. I’m all for allowing the games and denominations to be changed, but shouldn’t the regulators be involved when it comes to payout percentages???
— Gary from Charlotte, NC
From what I hear anything you can configure at the machine you can configure remotely through the server. This would include the theoretical return percentage. However most casinos report that changing the theoretical return of a slot machine necessitates a lot of paperwork.
Even if it were effortless to move the slot machine return up and down, it strikes me as a conspiracy theory to think the casinos would do that on a player by player basis. Living here in Vegas, I hear all kinds of theories about the lengths the casinos go to in order to win, like pumping in oxygen and playing a subsonic mantra that says "lose lose lose." These are just urban legends. Most casinos correctly believe that if you give the player a good experience and a fair gamble then he will keep coming back. As they say, you can only slaughter a sheep only once, but you can shear it many times. (My webmaster, Michael Bluejay, who is a vegetarian, tried to get me to use this analogy instead: "You can seize all of a sheep’s money only once, but you can force it to take you bowling many times.")
If a bank slot machines has signage that says "97.4% Return" what does that mean?
— Anonymous
According to the Nevada Gaming Control Boards that means that every slot machine in that bank must be set to a theoretical return of at least 97.4%. Popular opinion has it that only one machine must be set to 97.4%, or that the overall average must be 97.4%. However, I am taking a firm stand that both notions are wrong, at least here in Nevada.
When the house awards me free play on a slot machine, ex. $100, how much does it actually cost them?
— David from W. Palm Beach
It depends. If the slot play may be used in any machine in the casino, including video poker, then it can be worth 99 cents on the dollar or more, depending on the video poker offerings. For example, the MGM Mirage casinos award $1 in free slot play for every one point earned. It can be used in any machine in any casino connected to the MGM Mirage player card. Most MGM Mirage properties offer
9/6 Jacks or better, so the value of $1 in free slot play is worth 99.54 cents, with correct strategy.
However, sometimes free slot play must be done on particular promotional machines that don’t accept money. The value of this kind of free play is hard to estimate closely, but generally very little. For example, the Las Vegas World used to sell “$1000” vacation packages for $400. Of the alleged $1000 value $600 was in promotional slot machine play. In his book “Million Dollar Video Poker,” Bob Dancer writes that he did this deal numerous times over, and estimates the value of the free slot play to be about ten cents on the dollar.
If a multi-game video poker machine is set up with 12 games having theoretical returns from 97% to 99.5%, and I only play the game with the best return, what will the casino’s player tracking system show for my play? Will it show the theoretical return for the specific game I play, or the average return of all games available on the machine?
— James S. from Rock Island, IL
It will show the specific return of the game you played.
Is there a statistical test to check that a slot machine’s payout is correct? For example, the casino claims 93% payout, but a test shows 91% payout in 10,000 games. I think statistically, this may be okay, but I don’t know how the math would work.
— Mary Jo from Calgary
Let’s assume 10.8 for the standard deviation, which I get from the Red, White, and Blue game described in my
slot machine page. The standard deviation of the mean over n spins is standard deviation per bet divided by the square root of n. In this case, 10.8/10,000
0.5 = 0.108. The difference between 93% and 91% over 10,000 spins is just 18.5% of one standard deviation. To get the standard deviation of the mean to just 2% you would need a sample size of 291,600 spins. The standard deviation in slots will vary substantially, so take these figures with a grain of salt.
Do you know if there is any way to get the probability payout schedules for slot machines in Nevada? I called gaming and they told me it was confidential information. I am curious because at some point when playing a progressive slot machine, it must tilt into the players favor. And as a follow-up, what is the law on disclosure of probability tables. Thanks for the help in advance.
— Mark from Las Vegas
No, there isn’t. I don’t like it any more than you do. I think the player should be allowed to know the rules and/or the odds about what he is gambling on. Others have asked me if invoking the
state Freedom of Information Act 
. I tend to doubt it would help or apply. As far as I know, the only place with such a right to know might be Holland. I’m told in Amsterdam information about the virtual reel stripping is indicated in little cards on the machines. You could in theory calculate the odds with that information and the pay table.
