What is a bonus bet?
Bonus bet — A bonus bet is bookmaker credit similar to a free bet but with wagering or rollover requirements attached — much harder to extract cleanly.
A bonus bet is bookmaker credit that arrives in your account looking a lot like a free bet but with extra strings attached. The most common string is a wagering requirement: a £25 bonus bet with 3× wagering means you have to place £75 of qualifying bets before any of the bonus or its winnings convert to withdrawable cash. Sometimes the wagering is on the bonus only, sometimes on the bonus plus the deposit, sometimes restricted to certain odds bands or markets — every operator words it differently.
Bonus bets show up most often on the casino side of bookmaker accounts and from international operators where regulation differs. UK sportsbook welcome offers usually issue clean free bets without wagering, but a casino welcome offer almost always issues a bonus bet with heavy wagering. The label "bonus" rather than "free" is the marker to look for in the offer terms — and the language varies, with some operators calling them "bonus funds", "bonus credit" or "promo cash".
For matched betting, the practical question is whether the bonus bet is worth working through. The answer depends entirely on the wagering multiplier and the markets the wagering is allowed on. A 1× rollover at sensible odds is usually extractable through a single back-lay pairing, much like an SNR free bet. A 35× rollover on slot games — common on casino welcome offers — is rarely positive expected value once you account for the house edge across the required volume. Our bonus calculator covers the wagering-attached cases for sportsbook bonuses; for casino-side bonus bets the maths is unforgiving and is covered separately. The full sportsbook free-bet workflow is in our free bets guide, and the broader matched-betting structure is in our matched betting beginner guide.
Worked example
An operator issues a £25 bonus bet with 3× wagering on selections priced 1.80 or higher. Three rounds of £25 backs at, say, 2.0 with corresponding lays at the exchange — total volume £75 — produce a typical qualifying loss of around £1.50–£2 across the three. Whatever's left of the bonus plus winnings then converts to cash. Net extraction is in the £8–£12 range, much lower than a clean £25 SR free bet (which would extract around £23) and lower than even a £25 SNR (around £18).
By contrast: a £25 casino bonus with 35× wagering on slots requires £875 of slot stakes at a typical RTP of 96%. Expected loss across that volume is £35 — the bonus converts to a roughly negative £10 net result. Casino bonus bets with heavy wagering are not free-bet equivalents. They look generous on the offer page; the maths says otherwise.
Common mistake
Treating any bookmaker credit labelled "bonus" as if it were a free bet. Always read the offer terms for the wagering multiplier (1×, 3×, 35×), the markets it can be wagered on, the minimum odds, and the time limit. A 1× wagering bonus on sportsbook markets at sensible odds is close to a free bet in extraction terms. A 35× wagering bonus on slots is usually a negative-EV trap. The label is the same; the underlying maths is completely different.