Work out what an accumulator actually returns. Add as many selections as you like, in fractional or decimal odds, and mark any leg won, lost or void. Free, no signup.
A void selection does not kill an accumulator. If a match is postponed or a bet is settled void, the bookmaker prices that leg at 1.00 and it drops out. Your four-fold quietly becomes a treble, at shorter odds than you signed up for.
That is why the returns are lower than you expected, and it is the single most common reason people think a bookmaker has settled a bet wrongly. Mark the leg voidabove and you will see exactly what it does.
Multiply the decimal odds of every selection together. Three legs at 1.80, 2.10 and 1.50 give 1.80 × 2.10 × 1.50 = 5.67, so £10 returns £56.70 including your stake.
Fractional odds convert first: 5/2 becomes 3.50, 6/4 becomes 2.50, evens becomes 2.00. You can type either format into the calculator.
The bookmaker’s margin is charged on every leg, and it compounds. That is the reason accumulators are a losing proposition over time rather than an unlucky one — we tested every fold size across a decade of real closing prices and none of them held up out of sample. Odds-on four-folds came back at −17.7%.
Which does not mean don’t have one. It means bet it as the Saturday it is, not as a plan. 18+ · BeGambleAware.org
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