Who invented the slot machine?

Who invented the slot machine: Charles Fey

Most histories name Charles Fey as the inventor of the slot machine as we know it. His Liberty Bell had three spinning reels, five symbols (horseshoes, diamonds, spades, hearts and a Liberty Bell) and, crucially, paid winnings straight out of the machine. Three bells paid the top prize of ten nickels, or 50 cents. That combination of reels, symbols and an automatic payout is the blueprint every slot since has followed, from pub fruit machines to online video games.

Fey couldn't patent the Liberty Bell because gambling was illegal in California, according to Wikipedia's Charles Fey article (opens in a new tab). Competitors were free to copy it, which helps explain how quickly the design spread. The machine was itself banned in California after a few years, but demand elsewhere stayed high.

Charles Fey: the slot machine inventor's life

He's said to have changed his first name from August to Charles because he disliked the nickname "Gus". The details of his later career, including stories about other machines he built, are less well documented, so we've kept to the dates above.

When was the slot machine invented? Why the dates disagree

If you search for the year the slot machine was invented, you'll see 1887, 1891, 1895 and 1898 quoted with equal confidence. The sources really do disagree. Wikipedia's slot machine article says Fey devised the Liberty Bell at some time between 1887 and 1895, while its article on Fey himself says 1898. A working Liberty Bell dated 1899 survives in the Nevada State Museum's Fey Collection, so the machine certainly existed by then. Wikipedia's slot machine article (opens in a new tab) records both versions.

The fairest summary is that Fey's Liberty Bell appeared in San Francisco in the 1890s and was in production by 1899. Our history of slot machines sets out the full timeline.

Before the Liberty Bell: Sittman and Pitt's poker machine

The best-known forerunner came from Sittman and Pitt of Brooklyn, New York. Their machine used five drums holding 50 card faces and took a nickel a play. It didn't pay out by itself: prizes such as a free beer or cigars were handed over by the bar, depending on the establishment.

It also shows that the house edge is as old as the machines. The ten of spades and jack of hearts were left out of the deck, which doubled the odds against a royal flush. A standard deck has four possible royal flushes; removing two of those cards kills two of them, halving the number of winning combinations. Today the same idea is expressed openly as a published house edge or RTP, rather than hidden in the reels.

Wikipedia also credits a machine called Schultze's Horseshoe Slot Machine, from 1893, as the first with an automatic payout, and says Fey's own 1895 machine was a modified Horseshoe. Fey's contribution was to combine automatic payouts with simple reels that a machine could read, instead of a full card hand.

Mills Novelty, gum and the first fruit symbols

The design spread through Chicago's Mills Novelty Company. Herbert Mills produced a Liberty Bell in 1907; Wikipedia's slot machine article calls it the first copy, while the Mills Novelty Company article (opens in a new tab) says Mills collaborated with Fey. Mills had earlier built the Owl in 1897, described as the first mechanical upright cabinet slot machine.

Mills' Operator Bell is where the fruit comes from. It had an optional gum-vending attachment, and because the gum was fruit-flavoured, the reels gained lemons, cherries, oranges and plums. A stick of Bell-Fruit Gum pictured on the machine is said to be the origin of the BAR symbol still seen on classic slots today. Some operators leaned on the vending angle to argue the machines weren't gambling, though US courts treated some of them as gambling devices anyway.

Later slot machine inventions that shaped modern games

Fey invented the mechanical slot, but several later inventions shaped the games played today:

The Telnaes patent is the important one for today's games. With 256 virtual stops on each of three reels, a machine has 256 × 256 × 256 = 16,777,216 possible outcomes, far more than physical reels allow. Modern online slots go further, with outcomes picked by a tested random number generator. The first Megabucks jackpot, won on 1 February 1987, was $4,988,842.17, an early example of the progressive jackpot idea behind networked games such as Mega Moolah.

How the slot machine came to the UK

In Britain the slot became the fruit machine. The Gaming Act 1968 set rules for jackpot machines in casinos, bingo clubs and members' clubs, and for lower-stake AWP machines in pubs and arcades. British firms built their own traditions of holds and nudges; Electrocoin's Bar-X was created in 1981 and was in UK arcades by 1983. The Gaming Act 1968 page has the legal detail.

Since the Gambling Act 2005, machines have been sorted into categories A to D, and online slots have their own rules on speed, autoplay and stakes. The history of online casinos explains how the reels moved onto screens.

How to explore slot machine history yourself

1. Start with the Liberty Bell's basic design (three reels, five symbols, an automatic payout) and compare it with a modern three-reel game.
2. Read about the Sittman and Pitt machine to see how the house edge was built in by removing cards.
3. Follow the move from mechanical to electromechanical and video slots in the 1960s and 1970s.
4. Look at how random number generators and virtual reels changed the maths from the 1980s.
5. Check the UK side: the 1968 Act, the 2005 Act and today's online slot rules.
6. Visit our history hub for linked pages on each step.

Our casino history hub and the Paris Review's profile of Fey (opens in a new tab) are good starting points. Our guide to how online slots work shows where the story ends up.

Where to play slots today

This is a history page, so offers are secondary. If you'd like to try a modern descendant of Fey's machine, these partner offers are aimed at slots. 18+ and terms apply.

• Casumo: a 50% bonus up to £100 for new customers who opt in and deposit at least £20; wager the bonus 10x within 7 days, with a £5 maximum bet while it's active and game, play and payment restrictions.
• 10bet: a 100% match up to £25 for new UK customers who choose the casino bonus and deposit within 7 days; wager it 10x on slots within 3 days, maximum bonus winnings £1,000, and Skrill and Neteller deposits don't count.
• Coral: deposit and bet at least £10 on slots for 100 free spins at 10p each on selected games, accepted within 48 hours and used within 7 days, with no wagering on winnings; PayPal, Skrill, Neteller, Paysafe and prepaid cards don't qualify.

Today's slots still carry a house edge, just as the Liberty Bell did. More answers are in our casino questions section.

18+. Every casino game has a built-in house edge, so over time you should expect to lose what you stake. Set a budget before you play and stop when it’s gone: safer gambling tools and support. Free, confidential help: National Gambling Helpline 0808 8020 133.