8 Slot Machines Types and How they Differ

Under the Microscope: Eight types of slot machines found at today’s biggest online casinos.

8 Types of Slot Machines found at today's Biggest Online CasinosWe all have a basic idea of how slot machines work. They are all programmed with a computer chip containing a random number generator (RNG) that delivers absolutely random, unpredictable results. They all pay out, over a long period of time, based on a preset return to player (RTP). All slots feature reels with thematic symbols and a multitude of ways to create a payout.

But not all slot machines are created equally. The way we play them, the cost of doing so, and what we can expect to occur will differ greatly. With that in mind, we’ll take a closer look at eight slot machine types found at today’s biggest online casinos, and what makes them so different.

Types of Slot Machines at Today’s Biggest Online Casinos

After more than a century of innovation in the slot tech department, it’s no wonder there are so many different slots on the market today; all now available in the virtual realm via thousands of online casinos. We’ll briefly describe the eight most common slots now found online, as well as in land-based casinos.

1. Multi-Line Slot Machines

These are the most basic slots on the market, and the least common because of it. A multi-line slot is one that presents a specific number of pay lines, and requires a single coin to activate each line. The size of the coin cannot be changed. Thus, a nickel penny slot with 9 pay lines would cost $0.45 to play at full lines.

2. Multi-Line/Multi-Coin Slot Machines

Based on the preceding machines, these slots allow players to set the number of lines to activate, and the number of coins to be played per line. Players might choose 1, 2, or 3 coins per line. Common on classic 3-reel machines, a penny slot of this nature, with 5 lines available, could be played at full lines for $0.05, $0.10 or $0.15.

3. Straight Multiplier Slots

These games don’t require the activation of pay lines. Instead, a single coin activates all possible line combinations. Additional coins can be wagered, and will pay a multiplier that matches the number of coins. For instance, a combination that pays 15x for 1 coin will pay 30x for 2 coins, and 45x for 3 coins.

4. Bonus Multiplier Slots

These slot machines are the sequel to straight multiplier slots. Again, betting a single coin activates all possible winning combinations. However, betting max coins will deliver a higher payout. The straight multiplier might pay 15x for 1 coin, 30x for 2, and 45x for 3. Alternatively, a bonus multiplier will award a higher prize, perhaps 50x or 60x, for betting the max 3 coins.

5. Buy-a-Pay Slot Machines

Buy-a-Pay slot machines encourage players to invest additional coins in order to activate extra winning combinations and/or bonus features. More possible winning combinations equates to higher hit frequency and higher RTP. In these machines, the extra combinations are clearly displayed on the base screen.

6. Hidden Buy-a-Pays

Much like Buy-a-Pay slots, these games offer extra winning combinations and/or bonus features that can only be triggered if the player bets the maximum number of coins. Again, more combos/features means higher RTP. However, you’ll have to open the game’s rules/info screen and scour the pay table to learn about them.

7. Progressive Slot Machines

These popular slot machines carry a special jackpot prize that grows progressively larger until it’s won. Every wager placed on the game will contribute a small percentage of that bet to the progressive jackpot. Once the jackpot is struck, the game reseeds to its original value. Then the prize grows once more until it’s won again. It will take a specific series of symbols to either unleash the jackpot, or activate a bonus game in which the jackpot can be won.

8. Combination Slots

Last but not least, combination slots are any types of slot machines that fall into two or more of the above categories. It could be a bonus multiplier slot with a hidden buy-a-pay and progressive jackpot that players can only win by betting max coins.

Decisions, Decisions…

As for which slot machine types are best to play, that’s really up to your individual preference. The one thing all experts agree on is this. If there’s a way to increase the RTP by betting max coins, it’s best to invest the minimum amount of money to activate all features. Thus, you get the highest RTP at the lowest possible cost. And as always, remember to play responsibly!


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