Rule 4: How Late Withdrawals Eat Into a Five-Figure Return

The deduction that turned a £40,000 win into £28,000

A client of mine, years ago, watched his selection romp home at 5/1 in a fourteen-runner Goodwood handicap. He had £8,000 on it. The headline return, including stake, was £48,000. What landed in his account was £36,000. Two horses had been withdrawn at the start, the second one only minutes before the off. Rule 4 deductions of 20% applied. Twelve thousand pounds, taken straight out of a winning bet, before any tax, before any commission, before any cap. That is the moment most serious punters learn to take Rule 4 seriously. It is not a footnote. On a five-figure return, it is a working line item.

The frustration is that Rule 4 is mathematically fair. The bookmaker priced the original race based on the field, and a late withdrawal genuinely shortens every remaining horse’s chance of winning. The deduction recalibrates the price you took to reflect the price you should have been quoted in a smaller field. The fairness does not soften the blow when the cheque arrives.

This is a technical piece. The mechanics are stable across UK operators because they all use the Tattersalls table, but the way the rule applies to ante-post bets, to multiple withdrawals, and to bets struck at SP changes the maths in ways worth knowing before you settle a big position.

The Tattersalls deduction table from the inside

The Tattersalls Rule 4(c) deduction is keyed to the price of the withdrawn horse at the time of withdrawal. The table runs from very short prices producing very heavy deductions to long prices producing no deduction at all. A withdrawn horse priced at evens or shorter triggers a deduction of 90 pence in the pound on all winning bets in the affected market. A 2/1 withdrawal triggers 55p. A 5/2 triggers 40p. A 4/1 produces 25p. A 5/1 or 6/1 brings 15p. From 8/1 to 9/1 it is 10p. From 10/1 to 11/1 it drops to 5p. At 14/1 or longer the deduction is zero. Between these landmarks the table interpolates.

The arithmetic is on the winnings, not on the stake. A £5,000 win bet at 4/1 returns £25,000 including stake – £20,000 of profit. If a 5/2 chance is withdrawn and the 40p deduction triggers, the bookmaker keeps 40p of every pound of profit. The profit becomes £12,000 instead of £20,000. The stake comes back untouched. The settled return is £17,000. The deduction has eaten £8,000 from what looked like a £20,000 winner.

Two details often get missed. The first is that the price used is the bookmaker’s industry price at the moment the withdrawal is declared, not the morning price and not the eventual SP of the rest of the field. The second is that the table applies to the bet at the point of settlement regardless of whether your taken price was longer or shorter than SP. If you backed at 4/1 in the morning and SP comes back at 7/2 with a 5/2 withdrawal, your settlement is at 4/1 (the price you took) with the Rule 4 deduction applied to the 4/1 profit. BOG does not save you from Rule 4. They sit on different layers of the contract.

Compound Rule 4 when two horses are withdrawn

This is where the maths becomes harder than the table suggests. If two horses are withdrawn from the same market, the deductions stack, but they do not simply add. Each deduction is applied to the winnings that remain after the previous deduction. A 30p deduction followed by a 25p deduction does not produce a 55p deduction. It produces a deduction of 30p first, then 25p of what remains, which is 17.5p of the original – total 47.5p, not 55p.

The compounding cap is 90p in the pound across all stacked deductions on a single market. Once cumulative deductions hit 0.9, no further deduction applies. In a chaotic race where three horses are withdrawn late, the cap protects winning customers from total wipe-out but does not stop a stacked Rule 4 from eating a serious chunk of profit. I have seen 75p compound deductions on big-field handicaps where two clear market leaders both came out within an hour of the off. Anyone with a sizeable position on the eventual winner watched their return halve and halve again.

The timing matters. Bookmakers calculate the deduction based on the prices at the moment of each individual withdrawal, in sequence. If the first withdrawal causes the second-favourite to shorten, the second withdrawal of that now-shorter horse triggers a bigger deduction than would have applied if both had been withdrawn together. Stewards’ orders and trainer decisions in the last hour before a race can produce stacked Rule 4 patterns that look harsh on paper but follow the contract precisely.

Rule 4 on ante-post versus day-of-race bets

Ante-post bets are mostly insulated from Rule 4 by the way the contract is structured. When you back a horse ante-post under traditional terms and another runner is withdrawn before declarations, you typically lose your stake but receive no Rule 4 deduction either way – the loss is total and the rule is not relevant. When the market is NRNB-flagged, your stake comes back rather than being subject to Rule 4 on the rest of the field.

The interaction gets interesting on the day of the race. Once declarations are made and the field is set, day-of-race rules apply. If you held an ante-post NRNB bet through declarations and a non-runner is then announced between declarations and the off, the day-of-race Rule 4 deduction applies to your settlement just as if you had taken the price that morning. This is the part most punters miss. NRNB protects you from the horse you backed being scratched. It does not protect you from Rule 4 deductions caused by other horses being scratched after declarations.

Bets struck at SP carry their own version of the rule. Industry SP is formed in the on-course betting market in the minutes before the off, and that price already reflects any late withdrawals that happened before SP was set. A bet at SP therefore embeds the Rule 4 effect in the price itself rather than triggering a separate deduction. The exception is a withdrawal that happens at the start, after SP has formed. In that case Rule 4 applies to SP bets the same way it applies to fixed-price bets, using the withdrawn horse’s price at the moment of declaration.

A worked example on a large ante-post settlement

The clearest way to see the rule in action is to walk a single bet through. Suppose I take £10,000 each-way at 12/1 on a horse for the Cheltenham Festival Gold Cup, struck in NRNB conditions six weeks out. Place terms are 1/5 odds for the first three.

The horse wins. Without any Rule 4 deductions, my settlement is straightforward. The win half is £10,000 at 12/1, which returns £130,000 including stake. The place half is £10,000 at 12/5 (a fifth of 12/1), which returns £34,000 including stake. Total return is £164,000 on a £20,000 total stake, profit of £144,000.

Now add a 5/2 second-favourite withdrawn forty minutes before the off after declarations had been made. The Rule 4 deduction triggers at 40p in the pound on all winnings in the market. The £120,000 of profit on the win half becomes £72,000. The £24,000 of profit on the place half becomes £14,400. Stakes return untouched. The settled return is now £92,000 plus £24,400 of stake, totalling £116,400. Profit is £96,400, not £144,000. A single late withdrawal at a middling price has cost £47,600 of profit on a £20,000 stake. That is not a quibble. That is two-and-a-half times the original stake gone.

The same arithmetic plays out at smaller stakes but with less visible drama. At £100 each-way the same Rule 4 deduction would have cost roughly £476. Most punters at that stake size would absorb it without thinking too hard. The arithmetic, though, is identical. If anything sharpens the lesson, it is that the deduction scales linearly with stake and the absolute pound figure on a serious bet is what drives the trader’s behaviour. NRNB will save you from the horse you backed being scratched, but it does nothing about the rest of the field. Sizing a Cheltenham Festival position has to account for both rules at once.

Published by the High-Stakes Horse Racing Betting team.