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Horse Racing Rule 4 Deductions - Tattersalls R4 Explained


After a bookmaker has created a book of prices for a horse race, there is every possibility that a horse may be withdrawn (become a non runner) before the race starts. This can happen for many reasons, for example: the ground / going has changed dramatically and it no longer suits a particular horse or simply that a horse has become unwell (lame). As the bookmakers made up the original book based on all the horses taking part, the prices will now be incorrect.

Bookmakers are allowed to make deductions to any returns due on winning bets placed at a fixed price prior to the non runner(s) occuring and this is called a 'Rule 4 Deduction' or R4 for short. Deductions are based on a certain amount of pence in the pound, E.g. 20 pence in the pound and it is the price of the withdrawn horse which determines the amount of deduction. Rule 4 deductions are applied to both win bets and each way / place bets. It is only your winnings that are affected by the rule 4 deduction and not your original stake. If more than 1 horse is withdrawn, total deductions shall not exceed 75p in the pound.



Rule 4 Deductions

Odds of withdrawn horse
Deduction (pence in pound)
% of winnings
3/10 or shorter  
75p in £
Over 3/10 Up to and including 2/5
70p in £
Over 2/5 Up to and including 8/15
65p in £
Over 8/15 Up to and including 8/13
60p in £
Over 8/13 Up to and including 4/5
55p in £
Over 4/5 Up to and including 20/21
50p in £
Over 20/21 Up to and including 6/5
45p in £
Over 6/5 Up to and including 6/4
40p in £
Over 6/4 Up to and including 7/4
35p in £
Over 7/4 Up to and including 9/4
30p in £
Over 9/4 Up to and including 3/1
25p in £
Over 3/1 Up to and including 4/1
20p in £
Over 4/1 Up to and including 11/2
15p in £
Over 11/2 Up to and including 9/1
10p in £
Over 9/1 Up to and including 14/1
5p in £
Over 14/1  
No deduction made

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If there is enough time before the start of the horse race for bookmakers to create a new book after a horse is withdrawn, they will usually do so. In these cases the Rule 4 deductions will only apply to people who placed bets on horses at the original book prices before the non runner(s) occurred or people who took a price with a bookie soon after the non runner occurred and before the bookie could adjust their book to reflect the non runner(s). The good bookies clearly show when a R4 deduction may still apply to your bets if they are yet to update pricing. Be cautious as i've spotted a few that dont seem to give the warning! A lot of bookies go to SP only just after a non runner while they are adjusting their pricing - This seems sensible to me and clearly shows they are in the process of adjusting odds to reflect the NR.

If you place a bet on a horse after an earlier non runner and then an additional horse or horses are withdrawn before the start, your bet will be subject to Tattersalls r4 deductions on the later horses who become NR's.

So a key rule is to record the date/time that you place every horse racing bet. That way you can be sure any rule 4's applied are correct and valid.

Prefer decimal odds format? View our Betting Odds Converter for Fraction to Decimal and Decimal to Fraction conversion.




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