- Fact-checked by Josh Miller
- Edited by Diana Westfield
Fixed odds betting terminals are the machines humming away at the back of high street betting shops, mostly running electronic roulette. Most people know them as FOBTs, and the industry calls them B2 machines. For years you could stake up to £100 a spin on them, roughly every 20 seconds, and that turned them into one of the longest-running rows in British gambling. In April 2019 the maximum stake was cut to £2. The roulette itself didn’t change one bit, though, and its maths is the useful thing to understand.
What fixed odds betting terminals pay back
Roulette on these machines is the single-zero kind, so there are 37 numbers on the wheel and a single number pays 35 to 1. If the payout matched the odds it would be 36 to 1, and that one-number gap is the whole house edge: 2.7%, exactly what you’d face on a European wheel in a casino. Put £100 through the machine over an evening and the expectation is that it keeps about £2.70 of it, which is why you’ll see the payback quoted as 97.3%. The slot games on the same cabinet are a different story, and their paybacks, which are often lower than roulette’s, are tucked away in each game’s help screen if you go looking.
The name, by the way, isn’t hiding anything clever. “Fixed odds” only means each bet pays a set price that’s known before the spin, the same as at a roulette table, rather than a share of a pool.
What an hour costs at £2 and at £100
The average cost of any casino game comes from three numbers multiplied together: the stake, how many spins you play, and the house edge. The machines were built around a minimum of about 20 seconds per roulette game, so three spins a minute, or around 180 in an hour, is a fair assumption for someone playing steadily.
| Stake per spin | Staked in an hour | Average loss at 2.7% |
|---|---|---|
| £2 (since 2019) | £360 | about £9.70 |
| £10 | £1,800 | about £49 |
| £100 (before 2019) | £18,000 | about £486 |
That bottom row is the reason the stake was cut, and frankly it’s hard to argue with. An average of almost £500 an hour on a machine next to the bus stop is a lot, and the average is the gentle version: a bad hour at £100 a spin could easily cost a few thousand. At £2 the average is under a tenner. If you want the sum for your own stake and session length, or for any other game, the CasinoCalcs expected loss calculator does it in a second.
Why the swings feel bigger than 2.7%
Two point seven percent sounds like nothing, and on a single spin it nearly is. What makes these machines feel so much harsher is the pace. At 180 spins an hour a £50 balance played at £2 a time gets staked around seven times over, and the usual pattern isn’t a slow drift down to about £40.50, it’s winnings being fed straight back in until the balance hits zero. The edge does its work quietly; the speed and the habit of replaying wins do the rest. If you’re curious how that looks, the roulette simulator runs the same single-zero game with play money, and a few hundred spins on it is quite an education.
Staking systems don’t rescue it either. Doubling after a loss hits the £2 ceiling after a handful of spins, and the betting systems simulator shows every popular system ending up at that same 2.7%.
Staying in control
The machines will tell you how long you’ve been playing and how much you’ve spent, and most of them let you set a time or money limit before you start, a feature that’s far more useful than it sounds. Our view is simple: decide what an hour of entertainment is worth to you before you sit down, set the machine to it, and treat hitting it as the end of the session whether you’re up or down. If it’s stopped feeling like entertainment, the responsible gambling section has tools to check your spending and links to free, confidential help.
If you’re chasing losses on the machines, it’s time to stop. BeGambleAware.org offers free, confidential support, 24 hours a day.