Rule 4 Deductions

Rule 4 deductions are applied to bets when a horse is withdrawn from a race after the time of your bet wagered.

The rule 4 deduction is applied because it becomes easier for the other runners to win and the market is false without the withdrawn horse.

As each horse in the race will have one less to beat so it is more likely that it will win, then horse racing rule 4’s are applied.

In our Rule 4 Deductions guide, we explain the amount of money that is taken out of winnings to balance the effect of the withdrawn runner.

Rule 4 Deductions Chart

Here is the Rule 4 Deductions Chart which provides the amount of money deducted calculated against the betting odds.

1/9 or shorter 1.11 or shorter 90p in £1
2/11 to 2/17 1.18 to 1.12 85p in £1
1/4 to 1/5 1.25 to 1.20 80p in £1
3/10 to 2/7 1.30 to 1.29 75p in £1
2/5 to 1/3 1.40 to 1.33 70p in £1
8/15 to 4/9 1.53 to 1.45 65p in £1
8/13 to 4/7 1.62 to 1.57 60p in £1
4/5 to 4/6 1.80 to 1.66 55p in £1
20/21 to 5/6 1.95 to 1.83 50p in £1
Evens to 6/5 2.00 to 2.20 45p in £1
5/4 to 6/4 2.25 to 2.50 40p in £1
8/5 to 7/4 2.60 to 2.75 35p in £1
9/5 to 9/4 2.80 to 3.25 30p in £1
12/5 to 3/1 3.40 to 4.00 25p in £1
16/5 to 4/1 4.20 to 5.00 20p in £1
9/2 to 11/2 5.50 to 6.50 15p in £1
6/1 to 9/1 7.00 to 10.00 10p in £1
10/1 to 14/1 11.00 to 15.00 5p in £1
Over 14/1 Over 15.00 No deduction

Not all online sportsbook bookmakers make a deduction when Rule 4 is 5p in the pound.

What is a rule 4 deduction in the UK?

A Rule 4 deduction in the UK applies to winning bets and deducts a set value in pence out of every pound won.

The size of the deduction is determined by the betting odds of the horse withdrawn.

The level of the rule 4 deductions ranges from 90p in the pound at 1-9 or shorter to 5p in the pound at odds of 10-1 to 14-1.

Non-runners can hugely affect the payouts when the favourites are withdrawn.

What is the maximum rule 4 deduction?

The maximum rule 4 deduction is 90p per £1 winning return.

90% rule 4 deductions are only applied when the odds on the favourite are as short as 1-9 in the betting odds or several favourites are withdrawn.

The Rule 4 Deductions Chart helps you calculate the returns and help predict your potential payout.

How do you calculate Rule 4?

To calculate how much a rule 4 costs you need to change ‘pence’ to per cent and deduct that from your profit.

So here are some examples of how to calculate the deductions for horse racing rule 4’s:

  • A 10p rule 4 deduction on a winner will reduce your profit by 10%
  • A 20p rule 4 deduction on a winner will reduce your profit by 20%
  • A 40p rule 4 deduction on a winner will reduce your profit by 40%
  • A 50p rule 4 deduction on a winner will reduce your profit by 50%

Each price has a corresponding deduction on the Rule 4 Deductions table.

Whichever band the betting odds fall into, the corresponding deduction will be made against the odds that have already been taken.

Do Rule 4 Deductions Vary Between Bookmakers?

The Rule 4 price will be dependent on the betting odds at which the non-runner was trading at the time of its withdrawal and will be specific to the sports betting bookmaker.

It is unusual for rule 4 deductions to vary between online sportsbook bookmakers.

Bookmaker odds on horses when races are first priced up the day before the race can vary significantly, but rule 4 costs generally are very similar.

Does the best odds guaranteed bonus still apply after a rule 4?

Rule 4 still applies to bets placed under the best odds guaranteed bonus.

The bet will be paid out on whatever return is better – the original odds with the rule 4 applied or the starting price.

What is Rule 4 on Betfair Exchange?

The Betfair Exchange Rule 4 applies should a horse be declared a non-runner after bets have been placed.

The reduction factor will be applied to the prices of all Betfair Exchange matched bets, for both backers and layers.

If the reduction factor for the withdrawn horse is less than 2.5% a rule 4 deduction is not applied on the Betfair Exchange.


Rule 4 is an industry-wide deduction rule created for when there are non-runners in a horse race after the final declarations have been made.

Rule 4’s is simply a payout deduction that is made to winning bets, when the race is impacted by a horse not running.

As the Founder of British Racecourses, I have a life-long passion for horse racing and have loved the sport as long as I can remember. I am also a keen racehorse owner and have worked in the gambling industry for several years. I set up British Racecourses with the desire to share my passion for racing with other like-minded people.