A multiple is one bet with several definitions stacked inside it

Legs, and what each one does

The price on an accumulator is the product of the prices of its legs. Every leg must win for the bet to win, and each leg carries its own market definition, its own result source and its own rules. The arithmetic below is illustrative; the rule that governs which legs settle what way is the one on your account.

• Leg one — a match marketSettled on normal time by definition 1.90 Won
• Leg two — an outright marketSelection finished level with one other 3.40 Half
• Leg three — a race marketSelection did not start; withdrawal rule applies 4.00 Void
• Leg four — a totals marketSettled on the source result 2.10 Won

Three of the four states visible in that ledger — won, void and half — behave differently inside the multiplication, and the difference is not proportional to the stake. A won leg multiplies the running total, a void leg is removed and the multiplication continues without it, and a partly settled leg contributes at a reduced rate that the rules define.

The void leg

A void leg does not become a loss, and it does not become a win. The rules stated earlier apply: the leg is removed from the bet, and the remaining legs settle at their prices with the original stake.

The effect is easy to predict once it is written down. A leg priced at 4.00 that voids removes a factor of four from the product, so an accumulator that would have returned a large multiple returns a much smaller one — and the reduction is larger than the share of the stake that leg represented because the returns are multiplicative rather than additive. That is the whole mechanism, and it is why a single void leg can turn a five-fold return into a two-fold one.

The habit worth keeping is to check the price recomputation after a void leg, because the arithmetic is the part most often miscopied and the easiest to verify: multiply the surviving prices and compare.

A deduction on one leg

A deduction on one leg reduces that leg's price before the multiplication, which means it reduces the whole return by the same proportion. The leg is not removed and the bet does not void; the factor in the product is simply smaller than the slip showed.

It follows that deductions interact badly with multiples in a way that surprises people: a moderate deduction on one leg of an eight-fold removes a larger absolute sum than the same deduction on a single bet, because the factor is multiplied through every other leg. That is arithmetic rather than policy, and it is a reason to read the deduction scale before building a long multiple that includes a re-priced market.

Cashing out part of it

Cashing out a multiple is an offer on the whole ticket rather than on a leg, and it is priced against what the remaining legs are worth — which is itself a product of live prices. A partial cash-out, where the rules allow it, reduces the stake working on the ticket while leaving the bet alive.

Two things are worth knowing before using it. First, an accepted cash-out is final: the future settlement of the legs no longer changes what you were paid, so the whole tail of the accumulator is given up in exchange for the offer. Second, the offer is a price, not the current value of the bet — the difference is the margin, and it is why the figure moves against you while a leg is still running. Cash out has its own page here, because what it sells is not the bet but the right to its outcome.