# Accumulator

> An accumulator is one bet on several selections that must all win, with their decimal odds multiplied. Worked example and the each-way variant.

Source: https://eachwayatlas.uk/glossary/accumulator/
Updated: 2026-11-07

An accumulator, or acca, is one bet on several events in which every selection must win, and the decimal odds of the selections are multiplied together. A £2 stake on four selections priced 2.0, 3.0, 1.5 and 4.0 gives combined odds of 36.0. Each-way versions are on [each-way multiples](https://eachwayatlas.uk/each-way/each-way-multiples/).

## What an accumulator is

You make one bet and pick several selections. The bet pays only if all of them win, so a single loser ends it.

The reason people use it is the multiplication: each winner passes its whole return on to the next. The same feature is why it is harder to win than a single bet.

A double is the smallest accumulator, with two selections.

**The short version:** all selections must win, and their odds multiply.

## Example: four selections

Convert each price to decimal first; see [how to read odds](https://eachwayatlas.uk/each-way/how-to-read-odds/). Then multiply along the row.

**Example, win accumulator, £2 stake · Derived by us from the formula · checked 7 November 2026**

| Selection | Fractional | Decimal | Running product |
|---|---|---|---|
| Selection 1 | 1/1 | 2.0 | 2.0 |
| Selection 2 | 2/1 | 3.0 | 6.0 |
| Selection 3 | 1/2 | 1.5 | 9.0 |
| Selection 4 | 3/1 | 4.0 | 36.0 |

The return is £2 × 36.0 = £72.00, which is £70.00 profit. Remove any one winner and the return is nothing. These prices are invented for the sum and are not offers.

**The short version:** multiply the decimal prices, then multiply by the stake.

## The each-way variant

An each-way accumulator is two accumulators: a win accumulator and a place accumulator. It costs twice the unit stake; see [unit stake](https://eachwayatlas.uk/glossary/unit-stake/).

In the place accumulator every selection has to place, and each place part pays at that race's place fraction. A void selection is counted at 1.0; see [void bet](https://eachwayatlas.uk/glossary/void-bet/).

The cost and return sums for each-way multiples are on [each-way multiples](https://eachwayatlas.uk/each-way/each-way-multiples/).

**The short version:** each way doubles the cost, and every selection must place for the place part to pay.

## What we have and have not checked

The product rule is arithmetic that you can check on a calculator. The operators' own definitions are the part that needs a source.

**Operator accumulator rules · checked 7 November 2026**

| Fact to read | Where to read it | Status |
|---|---|---|
| The operator's definition of an accumulator | Operator betting rules, at least two, dated | Not verified |
| Each-way accumulator rules | Operator rules and the terms for the race | Not verified |

**The short version:** the example is our arithmetic; operator definitions are marked Not verified.