Wagering requirement calculator: what a casino bonus really costs

By the Rootan UK team· Checked 14 October 2026

A bonus only becomes cash once you have met its wagering requirement. Enter the terms to see how much you would need to bet, and the expected loss from the house edge along the way.

Bonus amount (£)Your deposit (£)Wagering requirement (x)Wagering applies toGame RTP (%)Game contribution to wagering (%)

Total you need to bet£1,000.00

Wagering counted towards the requirement£1,000.00

Expected loss while wagering (house edge)£40.00

Bonus minus expected loss£60.00

Example: a £100.00 bonus with 10x wagering on the bonus only means £1,000.00 of bets. At 96% RTP the expected loss is £40.00, so the bonus is worth about £60.00 on average. Turn on JavaScript to change the numbers.

How the numbers are worked out

Wagering counted = (bonus, or deposit + bonus) × the wagering multiple. If a game only counts part of each bet — say 10% for table games — you need to bet more: total bets = wagering counted ÷ contribution. The expected loss is total bets × (1 − RTP). The calculator uses the open-source rootan-probability library.

UK rules on wagering

Since 19 January 2026, casinos licensed in Great Britain cannot set wagering requirements above 10 times, or offer bonuses that mix casino with other gambling products. See our guide to the UK online casino rules for the details and other player protections.

What the calculator leaves out

It shows an average, not what will happen in one session. You can lose your whole balance before you finish wagering, especially on high-volatility slots. It also ignores maximum-win caps, bet limits and expiry dates, so read the full terms before you accept any bonus.

A quick rule of thumb

The higher the multiple and the lower the game contribution, the more a bonus costs. When "bonus minus expected loss" turns negative, the bonus is expected to cost more than it gives. If you notice you are betting more to "unlock" money, stop and see our safer gambling help.