Horse racing odds
The 120 per cent book means the prices across the entire field are compressed, which means every price is slightly lower than it should be in a fair market. A significant share of that GGY exists because punters accept worse odds than they need to. Horse racing odds comparison is the single most important habit a punter can develop, and it is also the one most punters neglect.
At the lower end, you find small-field Flat races — Group 1 contests with five or six runners where the form is well established and bookmakers compete aggressively on the headline price of the favourite. The difference between 3/1 and 7/2 is not dramatic on a single bet, but across 200 bets over a season it represents dozens of units of profit or loss. Checking the overround before you bet is not something most punters do, but it takes less than a minute with a calculator or an odds comparison site. Small-field races with well-fancied favourites tend to carry lower overrounds (closer to 110 per cent) because the market is more efficient and bookmakers compete harder on the headline price of the favourite. The difference between 5/1 and 6/1 on the same horse in the same race is a 20 per cent increase in profit — free money, essentially, for the 30 seconds it takes to check a second bookmaker.
The individual difference may be small — perhaps 5/1 versus 11/2 — but across hundreds of bets over a year, that cumulative margin is the difference between a profitable punter and a losing one. The take varies from state to state and the money is used to pay taxes, purse money for the horsemen, expenses at the track, and the track’s profit. If the exchange is at 7.0 and the bookmaker is at 6/1, the prices are closer, and after exchange commission the bookmaker might even be marginally better. Oddschecker is the most widely used in the UK and shows prices from all major bookmakers side by side, updated in near-real time. 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.
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.
Horse Racing Odds Comparison — More on this topic at horse racing bookmakers. Yet the majority of bettors place their bets with whichever app they last used, at whatever price happens to be on screen, without checking whether a better number is available elsewhere. @ScottyPick6 Scotty thank you so much for the winnings from the Saturday webinar. Biggest payout of my life! Took down that LP5 @BelmontStakes today!
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.
Best Odds Guaranteed is one of the most powerful tools available to horse racing punters, and it is routinely undervalued. Using the exchange as a benchmark — even if you ultimately bet with a bookmaker — is one of the most effective habits a punter can develop. The practical approach for most punters is to use both. If you back at 6.0 (5/1) and pay 5 per cent betting sites no gamstop commission on your winnings, your effective odds are 5.75 (approximately 19/4).
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. One person backs a horse to win; another lays it (bets against it winning). The betting exchange — Betfair being the dominant platform — operates on a fundamentally different model to a traditional bookmaker. Among fixed-odds bookmakers, bet365, Paddy Power, and William Hill tend to be competitive on feature races, while some smaller operators run wider books, particularly on less prominent meetings. By the time the race starts, competition among operators has usually tightened the market.