WHAT IS RULE 4?
Rule 4 is simply a deduction that is made to winning bets, when the race is impacted by a horse not running. It is a fair method of recalculating bets that have already been placed when suddenly a horse is withdrawn.
For example, if you bet on the second favourite to win a race at 5/1, but the favourite withdraws just before the race, then your chances of winning suddenly shoot up. To adjust for the non-runners, Rule 4 calculates what the true odds of each remaining horse now are.
Don’t worry, you won’t have to do anything when Rule 4 kicks in but it’s worth being aware of the clause in case you’re banking on a specific return from the race.
DOES RULE 4 AFFECT MY PAYOUT?
If Rule 4 is implemented in a race you have bet on then your payout might be affected. However, this depends on the horse that withdrew and the size of the race. For example, if a horse priced at 33/1 withdraws from a race involving 18 runners then Rule 4 would not be implemented, as the effect on the rest of the field is minimal.
However, were the 7/2 favourite to withdraw from a race at Cheltenham involving just seven runners then Rule 4 would kick in. Effectively, the shorter the odds of the non-runner, the bigger the Rule 4 deduction becomes.
Your settled bet will show the Rule 4 deduction which has been applied.
RULE 4 EXCEPTIONS
You can get a racing betting exception to Rule 4s if you bet on the ante-post markets. These are odds that are listed before the full race list is announced and are often used by punters looking to bet on races weeks and months in advance.
HOW TO CALCULATE RULE 4
Calculating Rule 4 can be tricky–and realistically you’re not expected to do it yourself! It all depends on the price of the non-runner and the strength of the field. However, as a general rule this table explains the basic Rule 4 deductions.
If you had a bet on a horse for £10 at 10/1 that went on to win, but in the same race the favourite (priced at 2/5) pulled out, your total return would be:
Pre 'Rule 4'
£10 x 10 = £100 (profit pre 'Rule 4')
£100 + £10 = £110 (total return pre 'Rule 4')
Post Rule 4
£100 less 70% (70p in the £) = £30 (profit post 'Rule 4')
£30 + £10 = £40 (total return post 'Rule 4')
In races where more than one horse is withdrawn, the deduction will not exceed 90p per £1 (or 90%).
You can also use the Paddy Power Bet Calculator and click on the Rule 4 button to help predict your potential payout.