Aintree Grand National Non Runners – Trends & Key Stats

The Grand National is the only UK race with a 40-runner cap, and that ceiling changes how non-runners work. When a declared horse is withdrawn, a reserve can step in to take its place — something that does not happen in any other race on the calendar. Each-way terms can shift as the field contracts, ante-post bettors face a unique form of exposure, and the sheer size of the field means that even with several non-runners, the race still goes to post with more horses than most events see in a week. Tracking non-runners in the final 48 hours before the National is not optional; it is the difference between informed betting and guesswork.

Forty go to post — fewer than forty were planned to. This article covers the reserve system, how withdrawals change each-way place terms, notable Grand National non-runners, and how to adjust your bets as the field takes shape.

The 40-Runner Limit and the Reserve System

The Grand National’s safety limit of 40 runners was introduced to manage the risk of the race’s unique demands — four miles and two furlongs over thirty fences, including Becher’s Brook, the Canal Turn and The Chair. Entries for the National far exceed 40. The five-day entry stage typically attracts upward of 100 entries, which are narrowed at the declaration stage by the handicapper’s weights and the trainer’s assessment of conditions.

When the field is declared and contains more than 40 runners, the lowest-weighted entries are balloted out. Those balloted horses sit in a reserve list, ranked by weight. If a declared runner is then withdrawn before the final forfeit stage, the first reserve steps in, inheriting the vacant spot in the field. This process continues until either the reserve list is exhausted or the race goes to post with 40 runners.

The reserve system means that a non-runner in the Grand National does not always shrink the field. It replaces one horse with another, which has two consequences for bettors. First, the market must reprice to account for the reserve’s arrival — a 66/1 reserve replacing a 10/1 non-runner changes the competitive landscape significantly. Second, each-way terms are tied to the number of runners at the off, not the number at declaration, so the terms hold as long as the field stays at or above the relevant threshold.

The contrast with the rest of the racing calendar is stark. In May 2025, nearly 28 per cent of all UK races had six or fewer runners — the second-worst figure in two decades. The Grand National, by design, runs at maximum capacity. The reserve system is part of that design, ensuring that the world’s most famous steeplechase fields a full lineup even when individual withdrawals occur.

How NR Change Each-Way Place Terms at Aintree

The Grand National is one of the few UK races where bookmakers pay out on the first four places at one-quarter the odds as standard, and some offer enhanced terms — five or six places, or one-fifth the odds — as promotional sweeteners. These terms are linked to the number of runners at the off. If non-runners reduce the field to fewer than 16, standard industry each-way terms drop to three places. That scenario is unlikely in the National itself, but it can happen in the supporting races on the Aintree card, where fields are smaller.

The more practical risk is subtler. Even when the field stays above the threshold, the withdrawal of a specific horse can change the each-way value of your selection. Backing a 20/1 shot each-way at one-quarter the odds is a fundamentally different bet depending on whether the horse is running against 39 rivals or 35. Fewer runners mean fewer horses between your selection and a place finish, which improves the place probability — but the each-way fraction remains the same, so the market adjusts by shortening the price. If you placed your bet before the non-runners were confirmed, you hold the old price at the improved probability, which can represent genuine value.

The flip side is that each-way bets on horses that were withdrawn are voided entirely, and any accumulator that included a National selection as a non-runner leg drops down by one fold. Given the number of accumulators built around the Grand National each year, the volume of restructured bets is significant.

Notable Grand National Non-Runners

The Grand National has a long history of high-profile withdrawals. Ante-post favourites have been pulled on the morning of the race due to going concerns, ground that turned soft overnight after a dry week, or minor injuries detected at the final veterinary inspection. Each withdrawal reshapes the betting landscape — and because the National attracts more casual punters than any other race, the market impact is amplified by the volume of bets placed before the withdrawal is announced.

The broader context adds weight to each individual scratch. The total number of horses running at least one race in Britain fell to 18,452 in 2024 — a one per cent decline from the previous year, with National Hunt recording a three per cent drop. Fewer horses in training means the pool from which the Grand National draws its entries is gradually shrinking, and each withdrawal from an already thinner talent base has a proportionally larger effect on the quality and competitiveness of the field.

For regular National bettors, the pattern is familiar. The five-day entry produces excitement, the declaration stage produces clarity, and the final 48 hours produce anxiety as non-runners trickle in and the reserve list activates. The horses that make it to post have survived a longer and more public filtering process than runners in any other race, which is part of what makes the National compelling — and part of what makes the non-runner risk so visible.

Adjusting Your National Bets After Withdrawals

When a non-runner is confirmed in the Grand National, the first question is whether it is your horse. If it is, your bet is voided (day-of-race) or lost (ante-post without NRNB). If it is not your horse, the second question is what the withdrawal means for the remaining field.

Check whether a reserve steps in, and if so, assess the reserve’s profile. A reserve entering the field at 100/1 has little impact on the competitive picture but does maintain the runner count and preserve each-way terms. A reserve entering at 25/1 — perhaps a horse that was balloted out on weights rather than ability — is a different proposition and may genuinely affect the chances of horses around it in the market.

Reassess the pace. The National’s extreme distance means early pace is critical — a field with three confirmed front-runners produces a different race from a field with one. If a pace-setter is withdrawn, the dynamics change just as they would in a flat race, except magnified over four miles. A slower early pace can bring more horses into contention at the business end, which alters the each-way equation. The habit of rechecking your analysis after every confirmed non-runner is more valuable in the National than in almost any other race, precisely because the stakes — financial and emotional — are higher.