Wagering requirements are how a “£50 free” bonus can end up worth nothing — and occasionally how it can be genuinely valuable. The difference is arithmetic that operators hope you won’t do. Let’s do it.

The definition, precisely

A wagering (or playthrough) requirement is the total amount you must stake before bonus winnings convert to withdrawable cash.

£20 bonus, 10x wagering = £200 in bets before you can cash out bonus winnings.

Watch the multiplier base: “10x bonus” on a £20 bonus is £200, but “10x deposit + bonus” on a £20 deposit + £20 bonus is £400 — twice the hurdle from the same headline number. Since the UKGC’s January 2026 rules, 10x is the legal maximum and deposit-plus-bonus structures have been largely squeezed out — any site offering 35x+ to UK players today is worth a licence check.

What wagering actually costs: the expected-value formula

Every bet you place while clearing wagering pays the house edge. So:

Expected cost of wagering ≈ wagering amount × house edge

Worked examples for a £50 bonus at 10x (£500 wagering):

Game usedRTPExpected cost of £500 wageringBonus worth (expected)
High RTP slot97%£15+£35
Average slot96%£20+£30
Low-variant slot92%£40+£10

The same bonus is worth three times more cleared on a 97% game than a 92% one — which is why our high RTP slots list matters most to bonus players, and why you should always check the RTP variant at your specific casino.

The honest caveat: these are averages. Clearing £500 of wagering on a volatile slot with a £50 starting balance busts more often than the expected value suggests. Positive EV is not a guarantee — treat bonuses as discounted entertainment, not income.

The four traps in the fine print

  1. Game contribution rates. Slots count 100%; roulette, blackjack and live games often count 10–20% or nothing. £100 on blackjack may clear £10 of wagering.
  2. Maximum bet while wagering. Usually £2–£5 per spin. Exceed it — even accidentally — and the casino may void the bonus and winnings. This is the most enforced term in the book.
  3. Expiry windows. Commonly 7–30 days. Unfinished wagering at expiry forfeits the bonus and its winnings.
  4. Excluded games and max win caps. Jackpot slots are usually excluded; some offers cap convertible winnings (e.g. £100 max), which slashes the real value.

The alternative: skip wagering entirely

The cleanest solution to wagering maths is a bonus with none. No-wagering offers pay winnings as immediately withdrawable cash — smaller headline numbers, dramatically higher real value for most players. We compare the genuine ones in our no wagering bonuses page.

If you do take a wagering bonus:

  • Read the contribution table before your first spin
  • Note the max bet and set your stake below it
  • Play a high-RTP, low-volatility eligible slot
  • Decide in advance to stop if the balance busts — never deposit to “rescue” a bonus

And remember the withdrawal test: a bonus cleared at a slow-paying casino is still slow money. Cross-check any bonus site against our fastest withdrawal rankings.