Ultimate Slots Guide
Learn everything there is to know about slots. This guide and our sub-guides discuss online slots, slot history, slot terminology, and slot strategy. Keep reading to learn more about slots.
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Slots (online slots and physical slot machines) are the most popular type of casino game in the U.S. In fact, a recent survey from Statista found that 48% of U.S. gamblers prefer playing slots over any other casino game with blackjack coming in second at 16%.
Because slots are such a popular form of gambling in the U.S, it’s important for players to understand what slots are, where they can legally play slots both in-person and online, how to play slots effectively, and other intricacies of this casino game.
This guide will cover everything there is to know about slots, including:
In addition to our deep dive into slots, you can find subsequent guides on different slot topics as well as more detailed information about playing online slots in New Jersey.
The Slot Machine
A slot machine is a traditional, coin-operated casino game with multiple reels that have a variety of symbols on them. The gambler activates the slot machine to spin the reels. The reels will eventually stop, creating a combination of symbols across the paylines. The resulting symbol combination determines if and how much the player wins.
The slot machine typically involves someone inputting bills or coins, which are then converted into slot credits that can be used to bet on the slot machine. Once the player has enough credits to meet the bet minimum for that slot machine, they can activate the reels by pressing a button or pulling a lever.
The slot machine is the world’s most popular casino game, and it comes with many different styles, themes, rules, and names. While we call it a slot machine, it is known by many other names throughout the world.
Whether you call them fruit machines, pokies, fruities, puggies, one-armed bandits, or slots — you’ve likely seen or played one of these popular games before, but do you know where slot machines originated, what makes them up, and how to play them?
The First Slot Machine
The term “slot machine” once referred to any machine that had a coin slot — including vending machines. However, as mechanical slot machines gained popularity, the term transitioned to the gambling game. So, where did slot machines come from?
The first known slot machine was invented in 1895 by Charles Fey, a car mechanic by trade, in San Francisco. “The Liberty Bell” was the name of the first slot machine, and Fey painted the following four symbols on three spinning reels.
- Liberty Bell
The original slot machine worked much like today’s slots. Once activated, the three reels spun and eventually stopped, resulting in a combination of symbols across the reels. If the player got three Liberty Bells, they won the jackpot of 50 cents.
For anyone interested in seeing the original Liberty Bell slot machine, you can find it in Reno, Nevada at the Liberty Belle Saloon & Restaurant.
Modern Slot Machines
The technology behind the first slot machine has changed drastically over the years, but the concept has remained. Modern slot machines in land-based casinos use digital technology, hardware, and computer software to manage the slot gameplay, as opposed to the mechanical wheels, levers, and gears in the traditional slot machine. While you can still find levered slot machines in today’s casinos, they are controlled by a central computer within the slot machine and not the mechanical sensors from Fey’s Liberty Bell and other early slot machines.
Modern slot machines convert coins and other inserted money into game credits, which are then used to activate motors within the machine to initiate the spinning reels. The machine’s internal computer uses a random number generator (RNG) to tell the reels when to stop. While the computer does determine where the reels will stop, the machine is not pre-programmed to payout at certain time intervals — it’s designed to produce the same randomized odds every spin.
The RNG spits out the results of your spin as soon as you pull the lever or press the button for that slot machine. It cycles through these number combinations 100+ times every second to produce consistently random results. Once your sequence is configured by the RNG, it communicates the symbol alignment automatically so that the slot machine can display your results via the stopped reels.
Example: Let’s use a traditional 3-reel slot machine to illustrate what happens when you play a modern slot machine at a land-based casino.
Step 1. Activate the game: Once you have enough credits to activate a spin, you place your bet and activate the spinning reels.
Step 2. RNG determines your sequence: Once triggered, the computer will use the RNG to record the next three numbers. Each of these numbers is usually quite large (i.e. 987,654,321) and is divided by a standard number to produce a final quotient. The computer executes this process automatically and produces your three-number sequence.
Step 3. Computer finds the corresponding reel location for your sequence: The computer will then use an internal sequence table to map the three numbers with the appropriate stop on the slot reel.
Step 4. The reels stop at the appropriate locations: Once the computer has randomly generated the number sequence and found the corresponding reel location, the computer causes the reels to stop at those placements. Once the reels stop, the symbols in the payline will determine whether it was a winning spin or not.
Components of Slot Machines
To this point, we’ve discussed the history of slot machines and how they work, but let’s take a quick look at the parts of a slot machine and the literal components that make up the land-based slot game.
Slot Candle (aka Tower Light): Slot machines will often have a light at the top known as the candle or tower light. These two colored lights are used to indicate the slot machine’s minimum denomination and to turn on when a player hits the service button signaling to the slot host that the player needs assistance.
Slot Pay Table: The slot pay table is the list of possible payouts from that slot based on the possible symbol combinations. This table will indicate how much you win when that specific sequence is displayed in the payline.
Slot Handle (aka Arm): The slot machine will typically have a handle also known as the arm or lever, which is used to start the round. Once pulled, the slot handle will start the round and the reels will begin to spin.
Bet Buttons: Modern slot machines will have buttons that signal specific actions to the slot machine. Typically, a slot machine will have a Bet Max and a Bet Min button, which are used to place your wager before the round.
Spin Button: While many modern slot machines will still have slot handles (arms), they are sometimes for display only. Most of these modern machines have a button that says “Spin,” which is what the player will need to press to start the round.
Casino Player Card Reader: Modern slot machines will also have an area on the slot for players to scan their casino rewards card. This feature allows players to gain rewards points when they play that slot. Rewards can be used for various benefits at the casino.
To learn more about the components of a slot machine, read our Guide to Slot Machine Parts.
Online slots are digital versions of the traditional slot machine and can be played for free or for real money at online casinos throughout the U.S. Online slot games are more dynamic and interactive than land-based slots, but their general gameplay remains the same.
Online slots are virtual games of luck made available by online casinos within their variety of casino games such as online blackjack, poker, sports betting, and more. Similar to land-based casinos, online slots make up the largest percentage of games in online casinos’ portfolio. Moreover, online slots are the most profitable and popular games.
In fact, many players will search for specific online slot titles, or they’ll seek online slot types such as progressive jackpots when deciding which online casino to join.
The process for playing an online slot is straightforward in most cases. The player will need to sign up at an online casino and deposit funds into their account. Then, they’ll decide on the online slot game they want to play. (Read our guide to Understand Online Slots)
Once they have opened the online slot window, they’ll place their bet and click the spin button to start the round. The digital reels with symbols will spin repeatedly and eventually stop. The corresponding symbols in the slot’s paylines will determine if and how much the player wins.
New players to online gambling often ask whether online slots are rigged and if they are safe, but these players need not worry because online slot games and the providers who design them are heavily regulated. These online slot games are tested to ensure fairness before they are approved for real money play.
As of August 2020, online slots for real money are legal only for players gambling at New Jersey online casinos, Pennsylvania online casinos, West Virginia online casinos, and Delaware online casinos.
History of Online Slots
Charles Fey and other mechanical slot manufacturers dominated the slot machine industry for the better part of a century (1895 – 1964). In 1964, electromechanical slots began to gain popularity throughout the country and specifically, Las Vegas. For many years, technological advancements led to changes in slot machines to increase the quality, breadth, and safety of slot gameplay.
In the 1990s, we saw the internet boom create rapid changes to our lifestyles. These changes also extended into the entertainment industry and gambling. Digital slot games — albeit limited — began popping up for at-home play.
In the early stages, these online slots were basically identical to traditional slots with the same symbols, number of reels, and paylines that were found on slots in land-based casinos. However, programmers and gaming developers began to push the envelope and add new types of gameplay, symbols, and interactivity that could not be done with physical slot machines.
Modern online slots are unlike anything you’ll find in a land-based casino. From unusual layouts and themes to interactive and advanced bonus games and features, these virtual casino games are designed to keep players engaged and entertained.
Legal Online Slots
One of the biggest questions people have about playing online slots is whether it is safe and legal. The good news is that it is completely legal under federal law to play online slots throughout the U.S.
The caveat to the legality of online slots in the U.S is that you can only play online slots for real money in the states that have legalized online gambling. At this point in time, the only states that permit gambling with real money on online slots are New Jersey, Pennsylvania, West Virginia, and Delaware.
Players in other U.S states can still play free online slots, but they are ineligible to win any real money.
Now, the general question of slot legality is easy — but, the harder questions are related to the fairness and regulation of online slot gameplay. Are online slot games regulated? How can you know for sure that the online slot isn’t rigged?
To answer the questions related to validity and fairness in a single online slot game, we need to look at the bigger picture, which is the overarching regulation and scrutiny that is placed on the online casino that makes the virtual slot available.
Every legal online casino is regulated by a larger government body whose sole job is to ensure the safety and fairness of gambling at that online casino. For example, the Division of Gaming Enforcement (DGE) regulates NJ online casinos, whereas the Pennsylvania Gaming Control Board (PGCB) governs online casinos in Pennsylvania.
These government authorities are constantly monitoring and auditing online casinos with verified third-party auditors. The online casino must remain compliant with all regulations and operating procedures issued by its governing authority.
This compliance extends to every game made available at an online casino — more specifically, it ensures that RNGs are actually random and communicated Payback Percentages are accurate. In addition to complying with government regulations, each game is tested by independent parties for fairness and randomness.
While these regulations and testing are designed to keep gameplay 100% fair, there are obviously instances of abuse and cheating — so, it’s important to gamble safely and diversify your gameplay to avoid suspicious activities. Moreover, you should only gamble real money at a legal and regulated U.S casino.
Playing Slots (Slot Strategy)
Playing slots in-person or online doesn’t require the same strategy or instincts that other casino games do — blackjack or poker, for example. However, having a general understanding of how slots work and what your odds are from one slot to the next can give you the opportunity to increase your chances of winning or even winning big, depending on your goals.
There are many myths when it comes to slot strategies, so we’ll focus on the factual advice that can help you play and win at slots.
First, know that slot spins are completely random.
It’s important to understand this point, so we’ll reiterate it. Legitimate online slots and slot machines at land-based casinos are always random — meaning that each spin is completely independent from the last. You may come across strategies that suggest otherwise, but spins on legal and regulated slot games are always random.
This reality is critical for understanding how to play slots successfully because there is no way to predict a future event based on past results. Many gamblers believe that if they have several losses in a row on a slot machine that they are “due” to win soon. However, this notion is incorrect.
If we know that every spin is independent, then we know there is no way to predict a subsequent action — which means winning at slots is 100% luck.
Set Personal Limits
Understanding the randomness of slots is crucial when playing, but to be successful at slots, you need to play wisely. Playing wisely often means having self-control and personal limits.
For example, you may want to set a loss limit when playing slots. A loss limit is a percentage of your bankroll that you are willing to lose, and once you’ve lost it, you commit to stop playing. Some people recommend a 20% loss limit for slots, which means that if you start with $50, you would stop playing once you’ve lost $10.
You may also want to set a win limit when playing slots to help you walk away in the green instead of continuing to push your luck — because remember that there is no such thing as a “hot machine” since every spin is completely random.
You may want to set a 20% win goal when you play slots, which would mean if you put that $50 in that you would stop once you get up to $60.
Setting limits when you play slots will help you capitalize on wins while mitigating losses.
Picking the Right Slot
Playing slots well is mostly about controlling what you can control. We already know that the spins are completely random — so you can’t control or predict slot results. But, you can set win and loss limits, and you can pick the slot you choose to wager your money on.
How do you pick the right slot?
- Choose slots with higher Return to Player (RTP): The RTP of a slot game differs from one slot to the next, so choosing one that is higher than the other means you have a greater chance of winning. Most slots have an RTP between 90% and 95%, but you can find some slots with an RTP of 98% or higher.
- Choose the variance that matches your goal: The variance of slots is also known as volatility or risk — and it’s what determines your odds of winning when you initiate a slot spin. A slot game with a low variance means that you have a higher chance of winning but will win smaller amounts. A slot machine with a high variance means you are less likely to win but are more likely to win higher amounts when you do. If you are looking for higher jackpots, you will want to pick a slot with high variance — if you want to win more often, look for low variance slots.
- Know the slots’ bonus features and rules: Many modern slots have bonus features and bonus rounds that provide an additional way to make money while playing at that slot other than the traditional paylines. Take the opportunity to look at the bonus features and the requirements for reaching those bonus features before you choose a slot. For example, many progressive slots won’t allow you to win the jackpot on a minimum bet — so, if you want to win big on that slot, you’ll need to bet more than the bet min.
Types of Slots
With hundreds of land-based casinos around the world and online casinos seemingly launching every month, there is no shortage of slots available to play. From classic 3-reel fruit slot games to pop-culture-themed electronic slots like Deal or No Deal, you have plenty of options for slot titles.
The specific theme of the slot is often less important than the type of slot. Let’s take a look at some of the popular types of slots available online and at land-based casinos.
Penny Slots are extremely popular slot games at casinos online and in-person because they are so affordable to play. While slots in general are cheaper casino games, the penny slot takes the cake with its low stakes — as little as a penny. Unfortunately, most penny slots do not pay well unless you wager more than the minimum bet, which means penny slots are good for entertainment and learning, but they’re not the best choice if you want to win a significant amount of money.
Most penny slots have a sliding scale for placing bets, which allows the gambler to choose anywhere between the minimum bet of a penny to the maximum — usually around $5 or more depending on the slot.
While penny slots are not known for producing huge winnings, there are progressive penny slots that can lead to massive jackpots. The caveat to winning these penny slot jackpots is that it often requires wagering considerably more than the minimum bet of a penny, and some require the max bet to play for the big jackpot.
When it comes to playing penny slots, it’s important to realize that even low wagers can add up quickly if you’re not careful. It’s estimated that an online slot can spin upwards of 600 times in an hour, meaning your penny wager could be up to $6 or more if you’re wagering more than the minimum.
Progressive Slots (Jackpot Slots) (sub-guide)
Progressive slots, also known as progressive jackpots or jackpot slots, are online slot games or live slot machines that offer a large payout (jackpot) that increases (progresses) every time a wager is made — only resetting once someone wins the jackpot.
The best way to think about a progressive slot is like a state lottery. Every week, numbers are drawn for a grand prize (jackpot). If nobody hits the jackpot, it increases for the next drawing. Once someone wins, it resets to a much lower prize.
Progressive slots do not play differently from any other slot game, but the odds of winning and the typical payout are usually lower than non-progressive slot games. The reason for this variance is that players are willing to win less money less frequently with the hopes of hitting the big payout. This makes progressive slots a much riskier slot game, but with higher reward if you are lucky enough to win the jackpot.
Many people are lured by the jackpot because it can be a substantial sum of money — upwards of $1 million or more in some cases. However, the odds of actually winning a progressive slot are slim, and the player will often need to have wagered the max bet to qualify for the progressive jackpot.
If you’re a risk-averse gambler, a progressive slot game may not be the best choice. But, if you are looking to roll the dice and can afford to lose your wagers, the reward could be astronomical.
Free Online Slots (sub-guide)
The next type of slot that you’ll often come across at online casinos is the free online slot game. A free online slot can have several different meanings, so it’s important to understand exactly what type of free slot you’re playing.
The two common types of free online slots that you may come across while gambling online are:
- Demo Slots: A demo slot is a free online slot that allows you to test the slot game using play (fake) money. You can freely play the slot game without wagering any real money, but you will be unable to earn any real money, as well. Demo slots are exactly what they sound like — a demonstration.
- Online Slot Bonuses: Online slot bonuses are often considered free slots because they allow the gambler to win real money on a slot without having to wager any of their own money. Most free online slot bonuses include free spins or a free bonus round. These are just two of the most common slot bonuses that offer a free slot spin or round.
Types of Slot Bonuses
Online casinos and land-based casinos both have reasons to incentivize players to wager on slots. As we’ve mentioned previously, slots are the most popular and most profitable casino game type. The more players choosing to gamble on slots often means more money for the casino.
To help motivate players to choose slots instead of blackjack, poker, or other casino table games, the casinos will often offer more bonuses for their slot games. Below are some of the most popular types of slot bonuses.
A slot jackpot is a large payout that can be won by hitting a specific combination of symbols on the slot reels. The odds of winning a slot jackpot will vary from slot to slot, but it’s often one of the biggest reasons players choose to gamble on a slot machine versus another casino game.
Whether it’s a progressive jackpot or a fixed jackpot amount, these prizes are often larger than any sum of money that player could win wagering on other casino games. One player recently hit a slot jackpot of $2 million.
Slot jackpots help casinos attract players with the hopes of hitting it big — even if the odds aren’t great.
Bonus Slot Features (Bonus Rounds)
Bonus features (bonus rounds) on a slot machine or online slot are extra layers within the slot game that provide more excitement and winning opportunities to the player. While these bonus features are baked into the slot’s payback percentage — they do offer value to the gambler by adding more excitement and variation to the gameplay.
Online slots and live slot machines often have unique bonus features to differentiate them from other slot themes. For instance, you may have seen a Wheel of Fortune slot machine at a casino that has a bonus round that lets the player spin a large wheel to win more than their original spin.
Another bonus feature is on the popular Deal or No Deal slot that has a bonus round where you can choose a box and play a round of Deal or No Deal for an added prize.
Bonus features on a slot make the game more fun and exciting, but they don’t necessarily make it more profitable than a regular slot game. In fact, slots with bonus features and bonus rounds often come at an extra cost (similar to progressive jackpots) because the prizes won in those bonus rounds must come from other, lost wagers.
Free spins are one of the most popular types of slot bonuses. They essentially give players a set number of credits that can be used on a specific slot game. Free spins are mostly used online, but some land-based casinos will also give players slot credits at their brick-and-mortar casinos.
There are a lot of reasons casinos give players free spins. To start, the odds of players winning anything substantial with free spins are marginal as they typically come with some type of play-through or wagering requirement. A wagering requirement on free spins means that the player must bet a certain number of times or a certain amount of money before they can claim any winnings from the free spin.
Casinos also love free spins because they get players to try the most profitable games — slots. The hope from casinos is that by introducing a player to a slot game, they can break the initial barrier and entice that player to continue playing on that slot after the free spins are used up.
Finally, casinos use free spins as a marketing tactic to attract and convert new players. This conversion technique is very popular with online casinos and is a great way for that casino to grow its player base. In fact, you will typically earn free spins at an online casino when you sign up and make your first deposit.
These free online slot spins are given in the forms of:
- No Deposit Slot Bonuses: Many online casinos will give you free spins in a welcome package just for registering at their casino. These free spins are given along with a no-deposit bonus and can be used without ever depositing money into your account. However, most online casinos will require you to deposit into your account or to hit a pretty high play-through requirement before you can withdraw any winnings from the free spins.
- First Deposit Slot Bonuses: Similar to a no-deposit bonus, a first-deposit bonus is a promotion that awards players for depositing a minimum amount of money into their online casino account. This bonus may include free spins and will often come with a wagering requirement that must be met before you can cash out any winnings from the free spins.
Glossary of Slot Terms
- 3-Reel Slot Machine: A basic slot machine with three reels and three rows of slot game symbols.
- 5-Reel Slot Machine: A slot machine with five reels and three or four rows of slot game symbols.
- Action: Slot action references the amount wagered with a slot spin and can also include the sum of previous winnings and losses.
- Active Payline: A player will often need to activate a payline with a wager to be eligible for winnings from that payline.
- Bet: A slot bet is a wager placed before activating the slot reels.
- Bet Max: A slot will usually have a “bet max” option, which is the largest amount of credits that a player can wager on a spin. The online slot or slot machine will typically have a “bet max” button that allows you to easily wager the maximum amount. Choosing to bet the maximum amount for a slot will give you the best odds of winning the most, and some slot jackpots require betting the maximum wager to be eligible to win.
- Bet Min: The “bet min” is the minimum amount that a player can wager for a slot.
- Bonus Feature: The bonus feature is also known as the bonus game, bonus round, or bonus free spins. These slot bonuses are often earned through gameplay, and once they’re triggered, the player has the chance to win additional money without wagering anything else.
- Carousel: A group of slot machines at a land-based casino is known as a carousel.
- Classic Slot: A traditional slot machine that describes the original 3-reel slot machine.
- Credits: Slot credits refer to your eligible bankroll at your current slot machine. Your coins or money are converted to credits, which you can then bet on that slot game.
- Freeplay: Freeplay, “free-to-play,” and “demo” refer to slot machines that can be played without wagering any real money.
- Hit Frequency: Hit frequency refers to the percentage of times a slot machine stops on a winning combination. For example, if a machine has a hit frequency of 6%, that slot machine lands on a winning combination 6% of the time.
- Icons: Slot icons are the game symbols that are used to determine winning combinations on the reels. Same as symbols.
- Jackpot: A slot’s jackpot is the top prize or payout from that slot machine.
- Payback Percentage: The payback percentage is the average percentage that a slot machine will pay its player back over time. Typically, this number will range from 90%-95%.
- Payline: The payline refers to the active line on the slot machine that determines your symbol combination.
- Payout: A slot payout refers to the winnings from a slot game, either from a single spin or the entirety of your play on that slot.
- Progressive Slot: Progressive slot machines are slot jackpots that continue to rise until they are won.
- Random Number Generator (RNG): Slots are random, and online slots use a technology known as RNG to randomly determine the sequence of a slot spin.
- Reels: The reels on a slot machine are the columns that spin during the slot round. The arrangement of symbols and paylines on the stopped reels determines your winnings.
- Return to Player (RTP): The RTP is the percentage of money that is returned to the player while gambling on a particular slot. If the RTP is 95% and you bet $1 100 times, you can expect to get $95 back, on average.
- Scatter: A scatter symbol is unique from other slot symbols on the reel because it activates unique bonuses or payouts regardless of other symbols.
- Symbols: Slot symbols are the icons on the slot machine that determine whether you win or not. Same as icons.
- Wilds: Wild symbols or wild icons on a slot machine can be substituted for any non-scatter or non-bonus symbol and can help you complete a winning combination on a payline.
- Win: Winning on a slot machine occurs when the reels stop and you hit a combination on an active payline that pays out.
Learn more about slot machine terminology in our Ultimate Glossary of Slot Terms.
Can You Win Playing Slots?
When you close your eyes and imagine being in a casino, the first image that probably comes to mind is the slot machine. Whether you’re imagining the flashing lights, the sound of spinning reels, the feeling of pulling the lever or winning symbols on a reel — the slot machine embodies the atmosphere of casinos and gambling almost better than any other casino game.
The big question people have about slots is whether they can actually win while playing them, and the truth is, sometimes.
Slots are entirely luck-driven as they are completely controlled by the computerized random number generator. As a result, the odds of winning are entirely based on the payback percentage of that slot game and the odds from the paytable.
With that in mind, playing slots is a lot like playing the lottery. And, just like the lottery — sometimes you can hit it big. Below are some stories from previous slot winners.