Win Caps Are Killing Your Bonuses
Lower wagering, worse bonuses: the hidden cost of maximum win limits
This piece is about the new wagering rules in the UK, but it’s relevant for players everywhere. Maximum win limits are now being actively used far beyond the UK.
The math is on your side. Almost.
Starting December 19, 2025, UK wagering requirements can’t exceed 10x the bonus amount.
With wagering this low, it doesn’t matter which slot you play or how you bet. The bonus is profitable long term. The math works in your favor. Positive expected value. Sounds great for both advantage players and recreational gamblers, right?
But the devil’s in the details. There’s one trick that turns a profitable bonus into a losing proposition, and operators are using it more and more. Maximum win limits.
What are win caps? Win caps are applied when playing with bonuses. This is a bonus restriction, similar to ‘30x wagering on bonus plus deposit’ or ‘maximum bet £5’. The idea is simple: you cannot win more than a predefined amount. For example, you deposit £100 and receive a £100 bonus. If the win cap is £300, after completing the wagering requirements you cannot withdraw more than that amount. Even if you win £1,000, your payout gets capped at £300.
What’s Changing and Why It Matters
The UK Gambling Commission (UKGC) is updating LCCP Social Responsibility Code 5.1.1. Maximum wagering is now 10x the bonus amount.
Right now you’ll see 30x on “deposit + bonus,” which equals 60x on just the bonus. After December 19th, it’s capped at 10x. That’s a 6x reduction in wagering.
The new rules also ban manipulation. Casinos used to advertise “10x wagering” but then add different contribution rates for different games. Roulette counts 10%, some slots 50%. This loophole let them push the effective wagering back up to 50x. That’s now illegal.
“These changes will better protect consumers from gambling harm and give consumers much better clarity on, and certainty of, offers,” says Tim Miller from UKGC.
But here’s the problem. The law doesn’t regulate win caps. UKGC requires that material terms (including wagering) be clear, prominent, and displayed alongside the main offer on all promo pages. Material terms include time limits, maximum bet size, and playthrough requirements. Win caps aren’t on that list.
So players will clear wagering requirements more often. But their winnings can get slashed. Win £4,000, receive £300. These bonuses can have negative value if you play the wrong games at the wrong stakes, even with low wagering.
How Did This Happen?
Before introducing the law, UKGC commissioned research from the Behavioural Insights Team on whether to lower wagering requirements. They also studied how well players understand wagering.
The research showed that:
Players consistently get it wrong. They overestimate their chances with high wagering (think 15%, reality 2%), and underestimate with low wagering (think 30%, could actually be 60%).
Wagering level doesn’t affect the decision to play. Same percentage played at 1x and 30x, despite the huge difference in generosity.
BIT recommended banning “bonus + deposit” language and limiting wagering to 1x. Their research didn’t account for win caps, which make the true value of a bonus even harder to understand1. So the terms will be clearer, but not better when win caps are involved.
Optimal Strategy Without Win Caps
Without win caps, there are two opposing strategies.
Strategy A: Maximum EV (Aggressive)
High volatility
Maximum bet size
Goal: hit a big win
Risk: you win big 1 out of 6 times
Example: Fruit Party slot, SD 23.22, £5 stake.
Result: EV £82.462, 16.63% chance to clear, average win £1,097.11
Strategy B: Steady Profit (Conservative)
Low volatility
Minimum bet size
Goal: guaranteed small profit
Risk: you win small amounts consistently
Example: Chicken Chase, £0.10 stake, SD 4.24:
Result: EV £64.82, 100% chance to clear, average win £164.82
That’s almost an 18% difference, and the gap widens with higher wagering.
You’re choosing between higher long-term profit with more bankroll risk (but less casino suspicion) versus guaranteed smaller profit with higher risk of getting flagged.
The first approach works for experienced players with stable bankrolls targeting lots of bonuses. The second is better for new players or those claiming fewer bonuses.
Optimal Strategy With Win Caps
When there’s a maximum win limit, the aggressive strategy stops working. Big wins get capped. Win £5,000, still receive £300. The conservative strategy still works with low wagering.
At higher wagering requirements, both strategies become unprofitable!
Now let’s compare the optimal strategy with win caps at 1x and 3x the bonus.
Now we see that the minimum volatility, minimum stake strategy is the only one that works. But even this strategy fails when the max win drops to 1x the bonus. This makes sense even without calculations. At 1x, the max win equals your deposit. If you deposit £100 and can only win £100, you obviously can’t profit. Best case, you break even.
Sometimes the max win isn’t tied to the bonus amount but fixed at a specific sum, like £200. In that case, you might think it’s better not to take the maximum possible bonus and reduce your deposit instead.
The best EV is still with the maximum deposit. This is because the average win of £160 doesn’t hit the £200 cap.
But if there’s a minimum bet requirement for the game, everything changes.
Playing at the minimum £0.10 bet, EV increases with deposit size. But for £1 and £5 bets, there’s an inflection point where larger deposits actually decrease bonus value.
What To Do In Practice
Look for bonuses without max win restrictions. Any way you play will have positive expected value (+EV).
Bonuses with win caps3 need to be played with minimum volatility at minimum stake.4
Avoid bonuses with 1x win caps. This is the worst possible scenario.
Win Caps Now Matter More Than Wagering
The new UKGC law is huge progress. 10x wagering instead of 60x really helps players, but not always. Win caps are a legal loophole operators are already exploiting, and I expect they’ll use it even more after the new rules kick in.
After December 19th, a bonus with 10x wagering and 1x win cap will be worse than the old 60x wagering bonus with no win limit.
The Behavioural Insights Team report didn’t investigate this maneuver, so I sent them my calculations and clarifications. Think they’ll respond? Drop a comment with your thoughts. While the rules are already adopted, maybe they’ll adjust them in the future and ban win restrictions.
Until then, read the terms carefully and understand your real odds. Good luck out there!
The same research noted it’s impossible to determine WR and EV knowing only a slot’s RTP.
Currency doesn’t matter. For a 100 deposit and 100 bonus, EV will be 82.56 whether that’s dollars, euros, or pounds.
We’re focusing on small win caps (3x-5x the bonus). Larger win caps would need a balanced volatility/stake strategy, but those offers are rare.
The chart shows that for a £10 deposit and £10 bonus, betting £1 is better than £0.10: £7.53 EV vs £6.51 EV. This happens because of the higher win cap to deposit ratio of 20x, compared to the 1x and 3x scenarios we looked at earlier.
What's a win cap?
There's a common promotion in meat space casinos to rebate a day's losses up to some limit, and that can be lucrative for an advantage player using a high-volatility machine despite resembling a bonus with a negative win cap. But perhaps I'm misunderstanding how a win cap is applied.