Rule 4 Deductions

Rule 4 covers the situation where a horse is withdrawn from a race, the odds for all bets placed on remaining horses are adjusted to account for the non-runner(s). This is because less horses in a race increases the probability of each remaining horse winning. A Rule 4 is normally expressed as x pence in the pound, and is an industry-wide rule.

You have elected to bet on Horse A @ 5/1 in the 2.30 at Ascot. There are only 3 runners in this particular race and later on in the day, Horse B @ 7/4 unfortunately has to withdraw from the race.
The race now becomes a 2 runner race and immediately your horse's chance of winning have increased from 1 in 3 runners to 1 in 2 runners. Once the non-runner is official we will revise the race at the earliest opportunity with new odds for the 2 remaining runners. Therefore with this in mind, the 5/1 taken earlier in the day is now no longer a fair reflection of Horse A's chances and some form of reduction is needed to compensate.

The quickest way to check whether this rule has been applied to your bet is by using our Account History or Settled bets options within the My Account area, a note will be displayed against the stake saying that Rule 4 has been applied, and the deduction amount:

Rule 4 deductions only occur after the final declarations for a race are made. Usually the final declaration stage is 24 hours before the race but it can be 48 hours before a race.

The amount taken from your winnings depends on how likely the horse(s) that were withdrawn from the race were to win.
For example, if the favourite in a race is withdrawn it will make it much easier for the second favourite to win. However, if an outsider is taken from the race then it will be still difficult for the second favourite to win as it still needs to beat the favourite.
The exact amount taken out of your winnings is based on the price of the withdrawn horse at the time of withdrawal. This is because the price equates to its chances of winning. The shorter its price, the bigger its chance of winning, and the larger the Rule 4 deduction is.
The below table shows the amount of the deductions based on the price of selections. These deductions are the amount of money that is taken from each £1 in winnings. Hence if you win £10 and there is a 10p Rule 4 deduction you will only receive £9 winnings.

If two or more horses are withdrawn, Rule 4 states the maximum deduction is 90p per £1 or 90%.

More than one Rule 4 deduction can apply if more than one horse is withdrawn from a race. For races where more than one horse is withdrawn, the deduction will not be larger than 90p per £1.

In the case of withdrawals in reformed markets, the total deduction over the two or more horses (i.e. one in the original and one in the reformed market) will be calculated on the prices in the original market. As an example;
You have bet on Horse A @ 5/1 in the 3pm at Ascot. There are only 4 runners in this particular race and later on in the day, Horse B unfortunately has to withdraw from the race. Horse C then refuses to go into the stalls so is also withdrawn from the race.
Horse B was withdrawn at 10am. At the time it was withdrawn, it was 7/4, and Horse C was 6/1 (before the race was revised). This means that all bets placed on any horse prior to 10am when Horse B was withdrawn are subject to a 45p Rule 4. This is made up of 35p for Horse B (7/4) and 10p for Horse C (6/1).
Horse C was withdrawn at 3pm, was 5/2 at the time and the market reformed at that point. All bets placed after the first Non-Runner at 10am and before 3pm are subject to a 25p rule 4.
All bets placed after the market was reformed again due to the non-runner at 3pm will not be subject to any deduction.

No, your full stake will be returned whatever the level of deduction on any winnings. The only instance where this wouldn't be the case would be in the event of any dead heats where dead heat rules would apply along with the rule 4.

If you take a price which is then subject to a Rule 4 deduction, the deduction will be applied unless the horse returns at a bigger SP. If this is the case the bet will return at the SP price without a Rule 4 deduction (unless the SP also has a Rule 4 applied as mentioned in the point above).

Still not clear?