What is Rule 4?

In horse racing, Rule 4 is an industry-standard rule, which governs the situation in which you have placed a win or each-way bet on a horse, and taken a price, but one or more horses are subsequently withdrawn from the race in question. Obviously, fewer horses in the race increases the likelihood of your horse winning, or being placed, so bookmakers can, quite legitimately, make a ‘Rule 4 deduction’ from your winnings, based on the price of the withdrawn horse(s) at the time of withdrawal. Rule 4 deductions are made on a sliding scale, ranging from 90p per £1 for a horse priced at 1/9, or shorter, to 5p per £1 for a horse priced between 10/1 and 14/1. If two or more horses are withdrawn from the race, more than one Rule 4 deduction may be applied but, in any case, the total deduction cannot ever be more than 90p per £1.