Horse racing odds
Around major meetings — Cheltenham, the Grand National, Royal Ascot — bookmakers offer boosted prices on selected runners. If the exchange offers 6.0 and the bookmaker offers 5/1, the bookmaker is competitive after commission. Instead of setting odds and accepting bets against them, the exchange matches punters on opposite sides of a bet. At the upper end, you find big-field handicaps with 20 or more runners, where each horse price can be inflated by a few ticks without any individual punter noticing the difference.
Across UK and Irish horse racing, typical bookmaker overrounds range from about 110 to 130 per cent. Understanding the typical ranges gives you a framework for evaluating whether the price you are being offered is competitive or padded. The margin a bookmaker builds into horse racing odds is not fixed. If you bet at a bookmaker with a consistently higher overround, you need a higher strike rate just to break even. The worst overrounds appear in ante-post markets, where the uncertainty justifies — in the bookmaker’s view — margins that can reach extraordinary levels. The overround also tells you something about the race itself.
In today’s day and age where automobiles have substituted the four legged animal, horses still retain importance. Dave Massey previews Saturday’s action at Aintree, selecting his best bets for the races at 1.15, 1.45, 2.25 and 3.00. Dave Chisnall spoke to kwiff on Friday afternoon just before he kicked off his Grand Slam of Darts qualifying campaign That small time investment — repeated across every bet you place — is the most reliable edge available to the average punter.
If the exchange offers 7.0 and the bookmaker offers 5/1, the bookmaker is taking a significantly larger margin on that runner, and you should either back on the exchange or find a bookmaker whose price is closer to the exchange level. On short-priced selections — odds-on or evens — the exchange commission can actually make the bookmaker price competitive or even better, because the commission is a fixed percentage of the profit regardless of the odds. The commission you pay on an exchange winning bet reduces your effective odds.
If you top non gamstop football betting sites back at 6.0 (5/1) and pay 5 per cent commission on your winnings, your effective odds are 5.75 (approximately 19/4). On a Monday afternoon novice hurdle at a minor track, liquidity is thin. Over time, backing at exchange odds rather than bookmaker odds produces a measurably higher return on investment, assuming you can find liquidity on your chosen market. The exchange takes a commission on the net winnings of the winning side, typically between 2 and 5 per cent depending on the user’s activity level. The overround on the Grand National ante-post market can reach as high as 180 per cent — a level that would be considered predatory in any raceday market. It varies by operator, by race type, and by the time of day.
First, it gives you a benchmark for whether the bookmaker prices are competitive. For any given horse, you can see the best available price highlighted, and the difference between the best and worst price is often two or three points of odds — the difference between 7/1 and 5/1 on the same horse in the same race. It does not require you to do anything special — just take an early price on a race where BOG is offered. Unlike free bets, which come with qualifying conditions and wagering requirements, BOG applies to every qualifying bet you place.
When should you use the exchange, and when should you use a bookmaker? There is a subtlety that experienced exchange users understand and newcomers often miss. Flutter Entertainment, which owns Betfair, reported global revenue of $14 billion in 2024 across 13.9 million average monthly users, but the exchange is only one part of that portfolio, and liquidity varies enormously by market. Hundreds of thousands of pounds are matched, and the spread between the back and lay prices is narrow. That difference — roughly 10 per cent on the individual price — is the cost of the bookmaker margin.
If you are betting early in the day and BOG is on offer, take the best available bookmaker price. If the exchange back price is 8.0 and the best bookmaker is offering 6/1, the bookmaker is taking a significantly wider margin on that horse. Here is the workflow that experienced punters follow, stripped of anything unnecessary. And some operators apply BOG only to bets placed after a certain time in the morning, which means very early ante-post-style wagers do not qualify.