Open a UK casino app at the moment, and there’s a decent chance something is waiting for you. A £1 drop, say. A few loyalty coins. A jackpot banner. It all feels quite generous.

The data tells a different story, and it starts with a tax rise most players never noticed.

On 1 April 2026, Remote Gaming Duty (RGD) went from 21% to 40%. You’d expect that to mean fewer promotions. What actually happened is odder: casinos started running more of them, and made each one smaller. We’ve been digging into why, and into whether the usual explanation is the whole story. It isn’t. UK online casino bonuses are shrinking.

The tax, in plain English

RGD is paid by the operator, not you. It’s charged on the profit a casino makes from online games played by UK customers (stakes in, minus winnings paid out), and it isn’t a cut of your deposit or your stake. The rise was announced in the Budget on 26 November 2025 and came into force the following April.

Here’s what it does to a casino with £100 of taxable profit. At 21% it owed £21 and kept £79. At 40% it owes £40 and keeps £60. That’s roughly a quarter less left over, before it has paid for software, staff, payment processing, affiliates or advertising.

The government’s reasoning was harm. Online casino games, slots especially, are seen as riskier than sports betting, which is why ministers dropped the idea of one merged remote gambling duty and gave casino the bigger increase. Sports betting gets its own rise later: from April 2027 online bets (UK horseracing aside) move from 15% to 25%.

One quirk we spotted along the way. The Office for Budget Responsibility notes that RGD includes the nominal stake value of a customer’s first use of any free plays. As we read it, that means free spins can carry a tax cost for the operator before anyone has won a penny. Worth knowing when you wonder why a casino is mean with them.

What the operators said they’d do

They were upfront about it. Within hours of the Budget, Entain said the tax changes (RGD and the later betting duty rise together) would add about £200 million a year to the cost of its UK and Ireland online business before any mitigation.

It said it expected to claw back around 25% of that through actions including cutting marketing and promotions. By March this year it was talking about offsetting more than half in 2027, and it took a £488 million non-cash impairment against its UK business.

Evoke, which owns William Hill, 888 and Mr Green, put its annual hit at £125 to £135 million once everything is in, and said mitigation would take away about half. It also talked about a significant reduction in UK investment.

None of that proves a single bonus was trimmed. It does show promotions were on the list from day one.

What UK online casino Bonuses data actually shows

The best evidence we’ve found comes from Jurnii, a promotions-tracking company, in a piece published by EGR Intel on 28 October. It’s written by Jurnii’s own chief commercial officer, so it’s a vendor looking at its own data, and it’s worth bearing in mind. That said, the method is clever.

Jurnii compared March (the last month before the rise) with the eight weeks after it, and with the stretch from late May to mid-October. Sportsbook offers on the same sites acted as a control, since betting duty hadn’t moved yet.

Where casino changed, and sport didn’t, the tax is the likeliest cause. Where both shifted together, the calendar probably did it (the end of the football season, the World Cup, the summer Flat season).

Here is what the numbers show:

• In the first eight weeks, the average casino brand ran 26% more existing-customer offers per day than in March. Sportsbook offers on the same sites slipped 2%.
• From late May, casino was still 17% above March. Sport was 1% up.
• Across the eight casino brands with enough valued offers to compare, the average offer fell from £5.66 to £4.25. The typical brand’s offer was 16% lower in the first eight weeks and 19% lower afterwards.
• In April and May, 53% of existing-customer casino offers were worth £1 or less, up from 42% in March. The median offer halved from £2 to £1, then drifted back to £2. Sport’s median stayed at £5 all the way through.

Almost all of the extra casino offers were either £1-or-less drops or loyalty-coin offers with no stated value. Offers worth more than £1 didn’t increase at all.

A fair warning on the sample: eight brands are not the whole market, and the report itself points out that one apparent signal (a fall in new casino launches) disappeared once sport was taken into account, because March has Cheltenham in it. So treat this as strong evidence of a direction, not an exact measure.

You’re the one paying.

The most telling detail is what didn’t move. Every casino welcome free-spins offer that was live in March was still there from late May onwards, including bet365’s £50, BetMGM’s £40, Sky Bet’s £25 and Unibet’s £20. The later dip in the median welcome offer came from more brands adding £10 deals, not from anyone cutting an existing one.

Operators have a fairly obvious reason to protect these offers. A welcome bonus is what gets you through the door, and it’s what shows up in comparison tables and affiliate rankings (including ours). Cutting it is public and risky. Shaving the £2 reward that lands in an existing customer’s account is almost invisible.

So a casino can look generous on the front page and be noticeably less so once you’ve signed up. If you only judge a site by its sign-up offer, you’re judging the part least likely to change.

Why a £1 drop isn’t really a £1 drop

Small rewards are clever marketing. They give you a reason to open the app. They keep the brand in front of you. And as Jurnii put it, they move the cost from the size of each offer to how many players actually take one up.

The catch is the loyalty-coin offers with no stated value. A coin isn’t cash. A point isn’t a pound. If a casino won’t tell you what something is worth, assume the answer is not much, and check the terms for expiry dates, conversion rates and whether you can actually withdraw it.

The jackpot twist

Jackpots grew from 2.4% of live casino offers in March to 4.7% from late May, and the number of brands pushing one went from four to seven by May. It’s tempting to read that as casinos swapping small bonuses for big prizes.

That isn’t quite what Jurnii found. Jackpots gained ground at the expense of prize draws, and drops, draws and jackpots together held at about a quarter of the offer shelf the whole time. Plus, many of these are pooled or network jackpots, like Unibet’s £1 million Hot Drops, rather than operator-funded bonuses. A big number in a banner makes a good advert, but it says little about your own chances.

Did the tax change what slots pay back?

Players worry about this most, so let’s be careful. RTP (return to player) is the share of stakes a game is designed to pay back over a huge number of spins. A 96% RTP slot has a 4% house edge in theory. Here’s what the duty does to that, using £100 of stakes:

The casino keeps 76p less on the same £100. So yes, there’s a financial incentive to look at lower-RTP versions of games, since many titles come in several approved configurations.

But there’s no evidence we can find that UK casinos have done this. Jurnii measures promotions, not payout settings. Operators also have plenty of other ways to cope: smaller bonuses, tougher supplier deals, cost cuts, thinner margins. If anything, one game supplier, Inspired Entertainment, reported its UK online revenue up 40% year on year in the second quarter, so players haven’t exactly walked away.

For now, the sensible habit is to check the RTP of the actual version you’re playing, because the same slot can have different returns at different casinos.

Two other forces were already squeezing bonuses

The tax didn’t arrive alone. From 19 January 2026, the Gambling Commission capped wagering requirements on bonus funds at 10x and banned mixed-product promotions, where you have to bet on sport and play slots to unlock an offer. A £10 bonus with 50x wagering used to mean £500 of play before you could withdraw. Now the ceiling is £100.

That’s a clear win for players. It also means operators lost an old trick: offering a big headline number and relying on the fine print to protect themselves. With less room to hide cost in the terms, and a bigger tax bill, the easiest lever left is the value of the reward itself.

The part nobody in the industry wants to say out loud

There’s an uncomfortable knock-on. Entain and Flutter’s UK boss both warned the Budget would hand a boost to unlicensed operators, who pay no UK duty and aren’t bound by UK bonus rules. Those firms have an obvious interest in making that argument, and we haven’t seen proof of a switch yet. But the logic isn’t hard to follow. If licensed sites trim everyday rewards while offshore sites advertise huge bonuses and no ID checks, the comparison starts to tilt.

It’s also exactly the kind of pitch we looked at in our recent piece on AI assistants recommending unlicensed casinos. A bigger bonus at a site that skips the safeguards isn’t a better deal. It’s a different, riskier one.

For context on the other side of the ledger: HMRC figures reported by Gambling.com show RGD made up half of UK gambling tax receipts between April and July 2026. The government expects the wider duty package to raise about £1.1 billion a year by 2029 to 2030. Whether the black-market warnings turn out to be right is something the next few years will answer.

April 2027 could bring another change

April 2027. Sports betting duty goes to 25%. Jurnii’s control group is about to stop being a control group, and we’ll find out whether sportsbook promotions get the same treatment.

Game settings. If operators start picking lower-RTP versions, that would matter far more to players than a shaved £1 drop. We’ll be watching for published return data.

Loyalty schemes. More tiers, challenges and points is the obvious direction. The question is whether any of it has a clear, withdrawable value.

Big versus small. Entain said it expects to gain market share as others leave the UK. If smaller operators can’t keep spending on acquisition, the market will get less competitive, and bonuses are rarely the first thing to get better in that situation.

How to judge a casino’s offers now

Stop counting banners. A busy promotions page tells you very little. Ask these instead:

• What is the reward actually worth in pounds, and is it cash, bonus money, points, or a chance at a prize?
• Does it need a deposit, and what are the wagering terms (the cap is now 10x)?
• Which games count, when does it expire, and is there a maximum you can withdraw?
• Can you switch off the promotional messages?

And one thing worth saying plainly. A smaller reward is never a reason to deposit more to make up the difference. Bonuses don’t change the odds of any game.

The tax has changed the economics of UK online casinos, and promotions are one of the first places it has shown up. More offers on the screen don’t necessarily mean more money in a player’s account, and that’s worth remembering as UK casinos settle into the new tax regime.

18+ only. Gambling carries financial risk and bonuses do not improve your odds. Play responsibly and never gamble money you can’t afford to lose.