SLOTS

Introduction

Slots are the most popular genre of casino games. Many consider slots to be more fun and exciting than other casino games due to the bonus rounds, creative themes, and chance of a large win off a small bet. Unfortunately slots are one of the worst mathematical bets in online casinos with a typical house edge of 3-6%.

Rules and Play

3-Reel Slots -- As the name implies, 3-reel slots have 3 reels. If the reels line up according to the listed paytable, you get the corresponding payout. The maximum payout often requires betting maximum coins (usually 3). There are many variations. Some 3-reel slots also have bonus rounds. If a certain symbol or combination of symbols appears, you enter a separate screen where you have the chance of a large win. You may have to pick a box, spin a wheel, or simply click a button.

Video Slots -- Standard video slots have 3 rows and 5 reels, for a total of 15 symbols. If you get 3 or more matching symbols, you receive the corresponding win. Wins pay from left to right, meaning 3 matching symbols in the first 3 reels is a win, but 3 matching symbols in the final three reels is not.

Video slots often have many lines of winning sequences. Line 1 to 3 are the lines of the three rows. Line 4 might be a diagonal sequence including reel 1 row 1, reel 2 row 2, reel 3 row 3, reel 4 row 2, and reel 5 row 1. There are 243 possible lines, but it is rare for more than 20 lines to be available. You can select 1 line, 20 lines, or any number in between. Each line represents a separate bet, so a 20-line bet is 20x larger than a 1-line bet.

Video slots may offer free spins and/or bonus rounds. Free spins are usually triggered by 3 or more scatter symbols. These scatters do not need to be on a winning line. They can be anywhere on the reels. If you get the scatters, the reels will spin on their own for a specified number of spins, usually 10-30. Wins are often doubled or tripled during the free spins, so much of the slot's overall payout may be in the free spins. Bonus rounds triggers vary. Like 3-reel slots, bonus rounds involve separate screen where you have the chance of a large win.

Fruit Machines -- Fruit machines refers to a type of European (often UK) 3-reel slots. The games usually have a variety of features, such as trails and nudges. Unlike other types of slots, there may be some strategy involved. Outcomes of fruit machines often have some non-random elements. True fruit machines are not common online, although Microgaming offers some AWP games.

Strategy

Most slots do not have strategy-related decisions. Simply spin and see if you have won or not. One aspect if slot play that is under your control is bet size and variance. Modifying variance can increase return when playing with bonuses. See the slot bonuses page for more detail.

After a spin is completed, some casino softwares give you the opportunity to double your win in a war-like game. The dealer and player both draw a card. If the player's card is higher, the win is doubled. If the dealer's card is higher, the player wins nothing. If the player and dealer tie, the original win is returned. You can double sequentially until reaching the maximum win. This double bet usually has no edge. Doubling can be useful when trying to reach a target gain for a sticky or Clearplay bonus. If doubling counts towards the wagering requirement, it can be used to dramatically reduce the expected loss per unit wagered. Note that video poker doubles may be restricted in the T&C. The game may not count towards wagering or may be banned alltogether when playing a bonus.

House Edge

Most online slots payout 94-97%, resulting in a house edge of 3-6%. This is roughly half the house edge of typical land-based slots. More specific information about individual softwares is below.

Wagerworks and Rival list payouts of their games. Wagerworks slots have a house edge of 2.5-5%, except for the maximum bet on 3-Reel Hold Up, which has a ~2% house edge. Rival slots have a 3-6% house edge.

Microgaming, Playtech, and Grand Virtual publish audit reports listing average slot payouts in the 95-96% range. This makes me believe the house edge of their slots varies from 3-6%, depending on the game. Cryptologic and Random Logic audit reports are typically a couple percent below the others in the 93-94% range, so the house edge of their slots is likely in the 5-8% range.

The house edge of Real Time Gaming slots is configurable. I believe there are 3 settings -- 2.5%, 5% (default), or an unknown higher percent. iNetBet's payout audits suggests they use the default 5% house edge.

Variance

Slots have a high variance, often higher than all table games and video poker options. This high a variance makes it difficult to complete a wagering requirement with slot play. You can reduce variance by decreasing bet size or choosing lower variance machines. Slots that have much of the overall payout in bonus rounds or other rare payouts tend to have the highest variance. While 3-reel slots and slots without bonus rounds tend to have lower variance.

With this high a variance, you may wish to use a non-traditional betting strategy. You can start out by selecting a normal or large bet size. If you get a big win, then you can switch to a small bet size and grind out the wagering, or switch to a lower variance game.