Acca Insurance Calculator: The Real Value of Accumulator Insurance (2026)
Acca insurance sounds like a safety net: if exactly one leg of your accumulator lets you down, the bookmaker gives your stake back, almost always as a free bet. This calculator works out what that offer is actually worth. Enter your legs, set the offer terms, and it shows the exact chance one leg loses, the free-bet value of the refund, and the honest EV, so you know if it is worth taking.
Everything runs in your browser, with no account. Here ACCA means an accumulator (a multi-leg bet), not the accounting qualification. Bookmaker offer terms change, so always check the current T&Cs before betting.
Acca insurance calculator
Your accumulator (5 legs)
Insurance offer terms
Set these to match your bookmaker's acca insurance. Common shape: 5+ legs, each at 1.20 or bigger, stake back as a free bet up to a cap.
The insurance is free, so it only ever adds value. But the EV without it is usually negative, because an acca stacks the bookmaker margin on every leg. Insurance softens the ride; it does not make a bad acca a good bet.
Insurance value by acca size
Using your legs, repeated to each size. The offer adds most when one leg losing is likely, which peaks at a middling number of legs.
| Legs | One loses | Insurance EV | Insured |
|---|---|---|---|
| 3 | 42.1% | — | Not covered |
| 4 | 27.6% | — | Not covered |
| 5 | 17.8% | +12.4% | Covered |
| 6 | 11.5% | +8.0% | Covered |
| 7 | 6.8% | +4.7% | Covered |
| 8 | 4.7% | +3.3% | Covered |
| 9 | 2.3% | +1.6% | Covered |
| 10 | 1.3% | +0.9% | Covered |
Acca insurance: what it is, and whether it is actually worth it
Acca insurance is one of the most common bookmaker offers, and one of the most misunderstood. The pitch is simple: build an accumulator, and if exactly one leg lets you down, you get your stake back. As of 2026 this free ToolsGambling calculator cuts through the marketing and shows what the offer is really worth, using the exact probability that one leg loses and the true, discounted value of a free-bet refund.
Why use the ToolsGambling acca insurance calculator
Most acca tools just add up your odds. The rare ones that touch insurance treat it as a vague bonus. This one values it properly: it computes the exact chance exactly one leg loses from your own probabilities, discounts the refund because it is a free bet not cash, checks whether your acca even qualifies, and gives an honest EV, including the uncomfortable truth that the acca itself is usually a losing bet.
The exact one-leg-loses probability
The insurance only pays when exactly one selection loses. This tool computes that probability precisely from your per-leg win chances, rather than guessing, so the value is real, not a rule of thumb.
Free bets are not cash
Almost every acca insurance refund is a free bet, which is worth less than its face value because the stake is not returned. The calculator discounts it, so the EV reflects what you can actually extract.
Model any bookmaker offer
Set the minimum legs, minimum odds per leg, refund cap and free-bet-or-cash toggle to match bet365, William Hill, Ladbrokes or any other offer. It even tells you when your acca does not qualify.
Honest about the acca itself
It shows the EV with and without insurance side by side. The offer adds value, but an accumulator stacks the margin on every leg, so the tool never pretends insurance turns a bad bet good.
What is acca insurance?
Acca insurance is a bookmaker promotion that refunds your stake if exactly one leg of a qualifying accumulator loses, while every other leg wins. The refund almost always comes as a free bet rather than cash, and the offer usually requires a minimum number of legs, a minimum price on each, and caps the refund at a set amount.
To be clear, ACCA here means an accumulator, a single bet combining several selections where all must win. It has nothing to do with the accounting qualification of the same name. If you searched for exam funding or the Big 4, this is not that page.
How acca insurance value is calculated
The value of the offer is the chance it pays out multiplied by what the refund is worth:
P(exactly 1 loses) × refund value = insurance EVI used to take every acca insurance offer going, feeling clever for the safety net. When I finally ran the numbers, the insurance was worth pennies on most of my slips, and the accas underneath were bleeding money on the margin. The offer was real, but it was lipstick on a bet I should not have been placing.
Which bookmakers offer acca insurance?
Acca insurance comes and goes as a promotion, but it has been a regular offer from most of the big UK books over the years. Names to look for include:
bet365, William Hill, Ladbrokes, Coral, Betfred, BetVictor, Paddy Power, Betfair. Terms differ and change often, so always read the current promotion before you bet. Note that Betfair's Acca Edge is a price boost, not stake-back insurance, so it works differently from the offers this calculator models.
Is acca insurance worth it?
The insurance itself is free, so taking it is never worse than not taking it, as long as your acca qualifies. Where the value lands depends on the odds: the more likely it is that exactly one leg loses, the more the refund is worth, which is why it matters most on mid-sized accas of five to seven legs at shortish prices.
The catch is the bet underneath. An accumulator multiplies the bookmaker margin across every leg, so the expected value is usually negative before insurance and still negative after. Acca insurance is a reason to prefer one book's version of an acca you were already placing, not a reason to place accas you otherwise would not.
Acca insurance terms
- A single bet combining several selections where every leg must win to return a payout.
- One selection within an accumulator; a five-fold acca has five legs.
- A refund of your stake, usually as a free bet, if exactly one leg of a qualifying acca loses.
- A bet token where the stake is not returned in a win, so it is worth less than its face value.
- The minimum price each leg must be for the acca to be eligible for the insurance offer.
- The average profit or loss of the bet over the long run, insurance included.
Accumulator (acca)
Leg
Acca insurance
Free bet
Qualifying odds
Expected value (EV)
More free betting tools on ToolsGambling.com
Acca insurance pairs with the tools that price accas and extract free-bet value. These free calculators help.
Bet responsibly
A safety net can make a risky acca feel safer than it is. Only stake what you can afford to lose and take a break if it stops being fun. Free, confidential help is at BeGambleAware.org.
Evgeniy Volkov
Verified ExpertFullstack developer with a background in mathematics. I build the calculators and game-style tools on ToolsGambling with Pixi.js and modern web tech, and every result uses transparent probability formulas you can verify yourself.
Acca insurance FAQ
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