You spot a £200 welcome bonus on a casino homepage and the number sticks. Then you open the terms and find a wagering requirement, a max bet rule, a seven-day clock and a cap on what you can withdraw. The £200 never becomes £200 in your pocket.
Bonuses are a product with a price, and you find that price in the terms. Read them before you deposit and you work out what an offer is worth to you.
When a casino credits your bonus, it adds bonus funds to a separate balance. You play with those funds, and you withdraw them after you meet the conditions attached to them.
Your own deposit stays yours. A £20 deposit matched at 100% gives you £20 in real money and £20 in bonus credit. You can withdraw the first £20 whenever you like. The second £20 comes with terms that control whether you ever take it out.
Free spin winnings land as bonus credit too. Spin a 50-spin offer worth 10p a spin, win £4, and that £4 arrives with the same wagering attached. Only what you win counts toward the balance.
Keep that split in mind and bonus offers read differently. Casinos advertise the headline figure as bonus credit, not cash.
The wagering requirement tells you how much you must bet before bonus funds turn into cash. A 35x requirement on a £20 bonus means £700 in qualifying stakes. A 40x requirement on a £200 bonus means £8,000.
The multiplier matters less than the total. A small bonus with a low playthrough can cost you less than a big bonus with a high one, and a bigger headline number can hide a worse deal.
If the arithmetic behind this feels fuzzy, clearing a playthrough requirement comes down to one sum: bonus amount times the multiplier, adjusted for what each game contributes.
Most casinos count slot play at 100% toward playthrough. Table games count at 10% or less, and some leave live dealer tables out.
Bet £700 on slots and you clear a 35x requirement on a £20 bonus. Bet the same £700 on roulette at 10% weighting and you have cleared £70 of it. Finishing the job at that rate takes £7,000 in roulette stakes.
Weighting rules like that make a slot-friendly bonus a poor fit if you play blackjack. Check the contribution table before you claim anything.
Most bonuses do not charge a fee. The strings attached to a bonus turn up as restrictions instead: games you cannot play, stakes that do not count toward playthrough, a window that closes before you finish.
Payment method exclusions belong here too. Casinos block PayPal, Paysafecard and some open banking deposits from bonus eligibility, because those routes make it easy to move money in and out. A debit card deposit keeps the bonus. An e-wallet deposit does not.
You find those exclusions in the terms, past the headline offer.
A max bet clause is the one that catches you. The terms might cap your stake at £5 per spin while a bonus is active. Spin £10 once and one spin cancels the bonus along with the winnings you built on it.
Time limits do similar damage. A 30-day expiry on a 35x requirement gives you room. A seven-day expiry on a 40x requirement does not, and a slow grind through low-volatility slots will not finish it.
You will find the max bet figure and the expiry date near the top of most bonus terms. Read both before you spin.
An operator might convert your winnings into cash, then cap what you can withdraw. A £500 maximum win clause on a £50 bonus means anything above £500 stays with the casino, however well you played.
Operators put a cap that swallows winnings near the bottom of the document, past the sections you want to skip. Check it before you claim. A bonus with a low cap and a high multiplier is the worst combination on the market.
Operators adjust payouts in other ways. Some apply a conversion rate that turns bonus funds into cash at a fraction of face value. Others deduct the bonus amount from your first withdrawal.
You will also meet adjustments that shrink a payout on sticky bonuses. Those funds attach to your balance and vanish when you withdraw, so the bonus never becomes cash at all. A sticky bonus suits extended play rather than a quick cashout.
Compare these rules across two or three operators and you will see large differences.
Bonus terms matter when the operator answers to a regulator. In the UK, that means the Gambling Commission. You can check whether GOKong Casino legit holds a UKGC licence on the Commission's public register, and the search takes two minutes.
A licensed operator publishes its terms, honours them and submits to dispute resolution. An unlicensed site writes whatever it likes and ignores you when you complain. The licence is the part of the deal you cannot afford to skip.
Register with GamStop if you want to block yourself from every UK-licensed site. You set deposit limits, loss limits and session reminders in your account, and they work whatever offer you claim.
Bonus documents run to several pages because regulators require disclosure, and reading terms without the jargon means translating a handful of phrases: wagering requirement, game weighting, maximum bet, maximum win.
Find those four numbers, write them down, and you can treat the rest as admin.
Take the playthrough total, apply the house edge of the games you plan to play, and you get an estimate of what the bonus costs in lost stakes on the way to clearing it.
A £100 bonus at 35x needs £3,500 in stakes. Play a slot with a 4% house edge and you expect to lose around £140 getting there. The bonus covers £100 of that at best, provided you finish before the clock runs out. Expect the real cost of a deposit match to fall somewhere between zero and the full value of the bonus.
Run the same sum on every offer you consider. A £200 bonus at 40x with a £500 win cap and slots-only weighting looks generous on the homepage, and you will see how modest it is once you price it.
Use that figure to decide whether an offer suits you. Claim bonuses you can clear, skip the ones you cannot, and read every welcome offer as a contract with terms you can check in advance.