Use the British Racecourses Accumulator Bet Calculator to work out the potential return and profit from an accumulator, also known as an acca.
Enter your selections, odds and stake into the calculator. You can use fractional or decimal odds and include settlement details such as each-way terms, Rule 4 deductions, non-runners and dead heats where applicable.
An accumulator combines several selections into one bet. Every selection must normally win for a standard win accumulator to succeed.
Use the free accumulator bet calculator now:
How to Use Our Accumulator Betting Calculator
To calculate an accumulator:
- Select Accumulator as the bet type.
- Choose the number of selections.
- Select win or each-way where applicable.
- Choose fractional or decimal odds.
- Enter the odds for each selection.
- Enter the result of each selection if you are checking a completed bet.
- Add any applicable Rule 4 deductions.
- Enter your stake.
- Check the total outlay, return and profit.
The calculator can be used before betting to check a potential payout or after the races to help check the settlement.
For other types of wagers, use the main horse racing Bet Calculator, which covers singles, doubles, trebles and larger combination bets.
However, many betting tipsters advise against accumulator bets because they are considered difficult to win.
All selections need to win or be placed, unlike a Lucky 15, Lucky 31, Lucky 63 and other types, where you only need one winner to make a return.
What Is an Accumulator Bet?
An accumulator combines several selections into one multiple bet.
The odds of each selection are combined to create one overall price.
For example, a four-horse win accumulator contains four selections. All four horses must win for the standard accumulator to succeed.
If the first three win but the fourth loses, the accumulator loses.
This differs from combination bets such as a Lucky 15, which divides four selections across 15 separate bets.
Our horse racing bet types guide explains how accumulators compare with Trixies, Patents, Yankees, Lucky 15s and other multiples.
How Is an Accumulator Calculated?
Decimal odds provide the simplest way to see how an accumulator is calculated.
Suppose four selections have the following decimal odds:
Selection 1: 2.00
Selection 2: 3.00
Selection 3: 2.50
Selection 4: 4.00
Multiply the four prices:
2.00 × 3.00 × 2.50 × 4.00 = 60.00
A £10 winning accumulator therefore returns:
£10 × 60.00 = £600
The £600 includes the original £10 stake.
The profit is:
£590
Every selection must win for this standard four-fold accumulator to produce that return.
How Do Fractional Odds Work in an Accumulator?
Fractional odds can also be used to calculate an accumulator.
Suppose you select three horses at:
1/1
2/1
4/1
First convert the prices to decimal odds.
1/1 odds become:
2.00
2/1 becomes:
3.00
4/1 odds become:
5.00
Multiply them:
2.00 × 3.00 × 5.00 = 30.00
A £10 winning multiple would therefore return:
£300
including the £10 stake.
Our fractional-to-decimal odds converter provides a complete conversion table, while the main betting odds guide explains how fractional and decimal prices work.
Accumulator Calculator Example
Consider a four-horse accumulator with the following prices:
Horse A: 5/2
Horse B: 7/2
Horse C: 4/1
Horse D: 10/1
In decimal form these are:
3.50
4.50
5.00
11.00
The combined decimal price is:
3.50 × 4.50 × 5.00 × 11.00 = 866.25
A £5 winning stake would therefore produce a potential return of:
£4,331.25
That large headline figure also illustrates the fundamental trade-off with accumulators.
All four horses need to win.
The potential payout becomes larger because several prices have been multiplied together, but every additional selection introduces another required result.
You can read more about the individual prices in our 5/2 odds, 7/2 odds and 10/1 odds explainers.
What Is a Four-Fold Accumulator?
A four-fold accumulator contains four selections.
All four need to produce the required result for a conventional four-fold to win.
For a win accumulator:
Selection 1 must win
Selection 2 must win
Selection 3 must win
Selection 4 must win
A £10 four-fold is one £10 bet.
This is different from a Yankee or Lucky 15.
A Yankee also uses four selections but creates 11 separate bets.
A Lucky 15 uses four selections to create 15 separate bets.
The difference has a major effect on the total stake and the number of winners required before a return becomes possible.
What Is a Five-Fold Accumulator?
A five-fold contains five selections combined into one bet.
All five must normally win for a standard win five-fold to succeed.
The calculation follows exactly the same principle:
Price 1 × Price 2 × Price 3 × Price 4 × Price 5
The resulting combined decimal price is then multiplied by the stake.
A six-fold uses six selections, a seven-fold uses seven and so on.
There is no need to calculate the combined price manually when using the accumulator calculator.
Accumulator Return Versus Profit
Return and profit mean different things.
Return is the complete amount paid back from a successful accumulator, including the returned stake.
Profit is the amount won above the original stake.
Suppose you place:
£20 accumulator at combined decimal odds of 15.00
The total return is:
£20 × 15.00 = £300
The profit is:
£300 – £20 = £280
The calculator displays these figures separately.
Why Accumulator Returns Can Become So Large
Accumulator returns increase quickly because every price is multiplied by the next.
Suppose four selections are all available at 3.00 decimal odds.
The combined price is:
3 × 3 × 3 × 3 = 81.00
A £10 accumulator therefore has a potential return of:
£810
Add a fifth selection at 3.00 and the combined price becomes:
243.00
The £10 potential return becomes:
£2,430
But the extra selection has not created free value.
The fifth selection is another result that must be correct before the accumulator wins.
Large potential returns should therefore be considered alongside the probability of every required outcome occurring.
Does Adding More Selections Improve an Accumulator?
No.
Adding another selection increases the potential payout because another price is incorporated into the multiple.
It also adds another outcome that needs to succeed.
This distinction matters because accumulator betting is often presented in terms of the potential jackpot rather than the probability of landing every leg.
Adding a horse simply because you want a bigger potential return does not make the underlying bet better.
Each selection should justify its place in the accumulator on its own merits.
Accumulators and Implied Probability
The combined price of an accumulator can be converted into raw implied probability.
Suppose the combined decimal price is:
20.00
The raw implied probability represented by that price is:
1 ÷ 20 × 100 = 5%
At decimal odds of:
100.00
the raw implied probability is:
1%
These figures come from the prices. They should not automatically be treated as the true probability of the accumulator winning.
Bookmaker prices include margin, and each individual selection still needs to be assessed.
Our bookmaker overround guide explains why market odds and true probability are not necessarily the same thing.
Can You Place an Each-Way Accumulator?
Yes. Many horse racing accumulators can be placed each-way.
An each-way accumulator consists of two multiples:
One win accumulator
One place accumulator
A £10 each-way accumulator therefore has a total stake of:
£20
The win part requires every selection to satisfy the win condition.
The place part requires every selection to satisfy the relevant place condition.
Place odds are calculated using the applicable place fraction for each selection.
This can make an each-way accumulator considerably more complicated to calculate manually.
Our each-way betting guide explains the basic structure, while Each-Way Value Explained looks more closely at prices, place fractions and extra places.
Each-Way Accumulator Example
Suppose you place:
£5 each-way four-fold
Your total stake is:
£10
There is a £5 win accumulator and a separate £5 place accumulator.
If every horse wins, both parts can succeed.
If every horse qualifies for a place but at least one does not win, the win accumulator loses but the place accumulator can still return.
If one horse fails to qualify for a place, the conventional place accumulator also loses.
The final return depends on the odds and place terms applying to each individual selection.
Use the calculator rather than assuming the place return is simply a fixed percentage of the win accumulator payout.
What Happens If One Selection Loses?
One losing selection defeats a standard accumulator.
Suppose you place a five-fold and the results are:
Winner
Winner
Winner
Loser
Winner
The accumulator loses because all five selections were required to win.
This is one of the main differences between a straightforward accumulator and a combination bet.
For example, a Lucky 15 divides four selections into singles, doubles, trebles and a four-fold. Some of those component bets can therefore win even when another selection loses.
Our Lucky 15 Calculator shows how that structure works.
What Happens If a Horse Is a Non-Runner?
A non-runner can alter an accumulator without necessarily causing the entire bet to lose.
For many conventional race-day multiples, a void selection is removed and the bet continues with the remaining legs.
A four-fold containing one void selection can therefore effectively become a treble.
Suppose the original selections are:
Horse A: Winner
Horse B: Non-runner
Horse C: Winner
Horse D: Winner
If Horse B is treated as void under the applicable rules, settlement can continue using Horses A, C and D.
The precise treatment depends on the terms applying to the bet.
Ante-post wagers can operate differently, so never assume every non-runner is automatically void.
How Does Rule 4 Affect an Accumulator?
Rule 4 deductions can affect individual horse racing selections within an accumulator when runners are withdrawn after fixed prices have been taken.
The deduction applies to the relevant winnings according to the applicable rules.
Because an accumulator combines several selections, an adjustment to one leg changes the eventual combined return.
The size of the deduction depends on the circumstances and the relevant price of the withdrawn horse.
Our Rule 4 deductions guide explains the calculation and deduction bands in more detail.
Where Rule 4 applies, enter the relevant deduction into the calculator rather than manually changing the original odds.
What Happens in a Dead Heat?
A dead heat occurs when two or more horses cannot be separated for a finishing position.
If one of your accumulator selections is involved in a dead heat, the settlement of that leg can affect the return from the complete multiple.
For a two-horse dead heat for first, the relevant stake carried into that selection is normally divided between the winning and losing portions for settlement purposes.
The calculation can become complicated because the dead-heat adjustment occurs within the multiple rather than simply at the end.
The accumulator calculator includes dead-heat options so you can enter the relevant result directly.
Best Odds Guaranteed and Accumulators
Best Odds Guaranteed can affect the settlement price of qualifying horse racing selections within an accumulator.
Suppose one horse is backed at 4/1 but wins at a larger Starting Price.
If that selection and wager qualify for BOG under the bookmaker’s current terms, the bigger qualifying price can affect the eventual accumulator return.
Eligibility varies between bookmakers, races, bet types and promotions.
BOG should therefore be treated as a settlement feature rather than assumed to apply to every accumulator.
Our Best Odds Guaranteed guide explains how the concession works.
Accumulator Insurance Explained
Some bookmakers periodically offer accumulator insurance or related promotions.
A typical promotion may provide some form of consolation when a specified multiple loses by one selection.
The exact qualifying number of legs, minimum odds, stake requirements, reward type and other conditions can vary.
These promotions change regularly.
Do not choose an accumulator or add an unnecessary selection purely to qualify for an insurance offer.
The underlying selections, odds and total stake still matter.
Check the bookmaker’s current terms before assuming a losing accumulator qualifies for any refund, free bet or other benefit.
Accumulator Versus Lucky 15
An accumulator and a Lucky 15 can contain the same four selections but work very differently.
A four-fold accumulator contains:
1 bet
All four selections need to win.
A Lucky 15 contains:
15 bets
These consist of four singles, six doubles, four trebles and one four-fold.
Because the Lucky 15 contains singles and smaller multiples, one or more successful selections can produce returns even if the four-fold itself loses.
The trade-off is total stake.
A £10 four-fold accumulator costs £10.
A £10 unit-stake Lucky 15 costs:
£150
because it contains 15 separate £10 bets.
This is why the unit stake and total outlay need to be distinguished when comparing multiple bets.
Accumulator Versus Yankee
A Yankee also uses four selections.
It contains:
6 doubles
4 trebles
1 four-fold
That creates 11 bets.
There are no singles.
A Yankee therefore provides more combination coverage than a single four-fold accumulator, but it also costs 11 times the unit stake.
Use our Yankee Bet Calculator when you want to calculate that structure.
Accumulator Versus Trixie
A Trixie uses three selections to create four bets:
3 doubles
1 treble
There are no singles.
A Trixie therefore provides several multiple combinations from three selections rather than putting all three into only one treble.
Our Trixie Bet Calculator calculates the four components together.
Accumulator Versus Patent
A Patent also uses three selections.
It contains:
3 singles
3 doubles
1 treble
That creates seven bets.
Because singles are included, one winner can produce a return.
The Patent Bet Calculator can be used when you want this additional coverage rather than a straightforward multiple.
Do Accumulators Offer Better Value?
Not automatically.
Combining several selections increases the potential payout, but it does not turn poor individual prices into good ones.
Suppose you believe a horse should be:
4/1
but the available price is:
3/1
Including that horse in an accumulator does not remove the price disadvantage.
The same principle applies to every leg.
The combined accumulator can only be assessed properly by considering the individual selections and prices that create it.
Our guide to finding value bets explains why the relationship between price and probability matters more than the size of the potential payout.
Why Comparing Accumulator Prices Matters
Small price differences can become more significant when several selections are combined.
Suppose four horses are available with different bookmakers.
If you automatically accept weaker odds on each selection, those differences compound when the prices are multiplied together.
Comparing the available odds before placing the accumulator can therefore materially affect the potential return.
British Racecourses compares operators from a racing perspective on our Best Horse Racing Betting Sites page.
The aim is not simply to find an operator offering an accumulator promotion. Odds, racing coverage, BOG, each-way terms, maximum payouts and account features can all matter.
Maximum Payouts and Large Accumulators
A successful accumulator can theoretically produce a very large return from a relatively modest stake.
That makes bookmaker maximum payout rules more relevant to accumulators than to many ordinary singles.
The figure shown by a calculator is the mathematical return from the odds and stake entered.
It does not override the bookmaker’s applicable maximum payout rules.
For high-odds or high-stake accumulators, check the relevant limits before placing the wager.
Our maximum payout betting sites comparison explains how these limits can differ.
Accumulators and Bankroll Management
A £10 accumulator has a £10 stake.
That simplicity can make the wager look relatively inexpensive compared with a Lucky 15 or Yankee carrying the same unit stake.
But accumulators should still form part of your overall betting outlay.
If you place:
£50 in singles
£20 in each-way bets
£20 in accumulators
your total amount staked is:
£90
The accumulator stake should not be ignored simply because it is additional to your main selections.
Our horse racing bankroll management guide explains how to track total exposure rather than looking at individual wagers in isolation.
Can You Use an Accumulator Across Different Sports?
Yes.
A conventional accumulator can include selections from different sporting events, provided the bookmaker permits the combination.
The mathematical principle remains the same: the prices are combined, and every required selection must succeed.
This calculator can therefore be used for football accumulators and other compatible fixed-odds multiples as well as horse racing accas.
For British Racecourses, our main focus remains horse racing, so the additional settlement guidance on this page concentrates on racing-specific issues such as Rule 4, non-runners, each-way terms and Best Odds Guaranteed.
Common Accumulator Calculator Mistakes
One common mistake is confusing return with profit.
If a £10 accumulator returns £500, the profit is £490 because the £500 return includes the original £10 stake.
Another is entering fractional odds as decimal prices or vice versa.
Check the odds format before calculating.
With each-way accumulators, remember the quoted stake applies separately to the win and place components. A £10 each-way accumulator therefore costs £20.
If a runner is withdrawn, use the correct non-runner and Rule 4 information rather than simply deleting the selection without checking the settlement rules.
Finally, do not enter the odds you expected to receive. Enter the prices at which the bet was actually placed or settled, depending on what you are calculating.
Is an Accumulator Bet Worth It?
The potential return alone does not determine whether an accumulator is worth placing.
An accumulator may offer a large payout because several outcomes all need to succeed.
The relevant questions are:
Would you back each selection individually at the available price?
Are you accepting competitive odds on every leg?
Do you understand how many selections need to win?
Is the total stake within your betting budget?
Do any promotional terms change the wager?
A £5 accumulator offering a four-figure potential return can look attractive on the bet slip. That headline figure does not tell you whether the individual selections represent value.
Accumulator Bet Calculator FAQs
What is an accumulator bet?
An accumulator combines several selections into one multiple. Every selection must normally succeed for a standard accumulator to win.
What is an acca?
Acca is simply a shortened name for an accumulator.
How do I calculate an accumulator?
Multiply the decimal odds of every selection together, then multiply the resulting combined price by the stake.
The British Racecourses accumulator calculator does this automatically.
How many selections are in an accumulator?
Accumulator is commonly used for a multiple containing four or more selections. A four-selection accumulator is a four-fold, five selections make a five-fold and so on.
Do all accumulator selections have to win?
For a conventional win accumulator, yes. Every selection needs to win unless a leg is treated differently under the applicable settlement rules, such as a void non-runner.
What happens if one selection loses?
A standard accumulator loses if one required selection loses.
What happens if one horse is a non-runner?
A conventional race-day accumulator can continue with the remaining selections when a leg is treated as void. Check the rules applying to the wager because ante-post and promotional bets can operate differently.
Can an accumulator be each-way?
Yes. An each-way accumulator contains a win multiple and a place multiple, doubling the quoted unit stake.
How much does a £10 each-way accumulator cost?
£20. There is a £10 win accumulator and a £10 place accumulator.
Can Rule 4 affect an accumulator?
Yes. A Rule 4 deduction on an eligible horse racing leg can change the eventual return from the complete accumulator.
Does Best Odds Guaranteed apply to accumulators?
It can apply to qualifying selections and wagers, but bookmaker terms vary. Check the current BOG conditions applying to the bet.
Can I calculate fractional accumulator odds?
Yes. Select fractional odds and enter the price for each selection. The calculator will work out the combined return.
Can I calculate decimal accumulator odds?
Yes. Select decimal odds and enter each decimal price.
What is the difference between an accumulator and a Lucky 15?
An accumulator is one multiple requiring all selections to succeed. A Lucky 15 contains 15 separate bets across four selections, including singles, doubles, trebles and a four-fold.
Is an accumulator the same as a multiple?
An accumulator is a type of multiple bet. Multiple is the broader term for wagers that combine more than one selection.
Does adding more selections make an accumulator better?
No. It increases the potential return, but it also adds another required outcome. Adding selections does not create value by itself.
Can I use the calculator after the races have finished?
Yes. Enter the actual results and relevant settlement information to check the expected return.
Why is my bookmaker return different from the calculator?
Check the odds entered, stake, each-way terms, non-runners, Rule 4 deductions, dead heats, BOG settlement and any applicable bookmaker promotion.
The bookmaker’s official settlement remains the final account transaction.
Responsible Betting
Accumulator bets can display large potential payouts from relatively small stakes.
The size of that payout does not make the bet more likely to win.
Every additional leg creates another result that must succeed.
Check the total stake, compare the prices and avoid adding selections purely to increase the headline return.
Set a betting budget and do not increase stakes to recover previous losses.
Summary
The British Racecourses Accumulator Bet Calculator works out the potential return and profit from an accumulator bet.
Enter the number of selections, odds, outcomes and stake to calculate the wager. Racing-specific settlement information, such as each-way terms, Rule 4 deductions, dead heats, and non-runners, can also affect the final return.
A standard accumulator combines several selections into one bet. Every selection normally needs to win.
The potential return rises as more prices are multiplied together, but every extra leg also introduces another result that must succeed.
Use the calculator for the arithmetic. Use our betting odds guide to understand the prices and our horse racing bet types guide when deciding how an accumulator differs from other multiple bets.
