Why Is the Same Horse a Different Price at Each Bookmaker?

Because they are not all taking the same cut, and the difference between them is larger than almost anyone assumes.

Every bookmaker looks at the same race, and mostly agrees about which horse is likely to win. What differs is how much they add on top for taking your bet. One firm might build a book that comes to a seventh more than a fair market. Another might build one that comes to nearly a third more. Same horses, same race, same afternoon.

That difference does not show up anywhere on your slip. It is inside the prices, which is why you can only see it by adding a whole race up and comparing.

So we did that, on every race we hold, for every bookmaker that priced it.

What each bookmaker charged

Read the overround column. The tightest book on the list charges roughly half what the loosest does, and the ordering is remarkably stable from one day to the next.

Two things about how this is built, because on a table naming real firms the method matters as much as the numbers.

It uses one book per race per firm, taken before the race, and only when the firm priced every runner. A book missing three horses is not a cheap book, it is a partial one, and counting it would flatter whoever quotes least.

Firms do not all price the same races, so ranking them on everything they happen to have covered confounds charging less with only pricing the easy ones. The table above uses the races that every listed book priced in full.

We should also say what this table is not. 23 days of collection is not a season. Books a fraction of a point apart are level, and the table marks them that way rather than inventing an order the sample cannot support. The two ends of it are a different matter: that gap is far too wide to be noise.

One more thing worth stating plainly. Several firms in that table pay us through affiliate links, and the tightest book on the list is not one of them. Our partners sit scattered through the middle, and the first firm ever to pay us appears in the bottom half. The table is printed in the order the data produced.

There are also fewer bookmakers than there appear to be

While measuring the prices we checked something else: how often two brands post exactly the same number.

The top row is the clear case. Identical to the penny, thousands of times over, and matching on every single runner on whole days at a time, is not two firms independently arriving at the same view. It is one price feed wearing two names. No other pair on the list has managed a clean day.

The other two need a more careful sentence, and we would rather write it than round it up. Agreeing on nineteen runners in twenty is not one feed. It is also not two firms pricing independently, because the closest pair that sits below our duplicate threshold agrees on 88.9% of the runners they both price, measured across 2,409 of them. Those two pairs sit in a gap of their own, several points clear of everyone else and too close together for 23 days of data to separate.

This matters for a claim you will see everywhere, including on this site's own racecards: best price across N bookmakers. If two of those N move together, the number of independent opinions behind the badge is smaller than the badge says. We detect these pairs by comparing every pair of books on the list rather than by keeping a list of known ones, so a new one shows up on its own.

None of that is a scandal. Plenty of brands buy their pricing in or share a parent, and nobody hides it. It is simply worth knowing that shopping between two names on one feed is not shopping around at all.

What any of those books costs you in the end comes back to how much of your stake the bookmakers keep, which is the number the whole table is ranked on.

A word on all of this

None of these pages is a tip, and none describes a way to win. They describe what betting costs, which is a different and more reliable subject. If your betting has stopped being fun, BeGambleAware has free, confidential help, and the National Gambling Helpline is on 0808 8020 133.

Common questions

Why do bookmakers have different odds on the same horse?

Partly because they judge the race slightly differently, but mostly because they add different amounts on top for taking the bet. Measured over a fortnight, the tightest book on our list charges around half what the loosest does.

Which bookmaker has the best odds?

On our measurements the tightest book overall is the sportsbook run by Smarkets, which is not one of our affiliate partners. Tightest overall is not the same as best on any given horse: a loose book can still post the top price on one runner.

Is this the same as the best-price comparison on your racecards?

No, and they answer different questions. The racecard shows who is offering the biggest price on one horse right now. This shows who takes the least out of a race as a whole, over many races.

How many bookmakers are there really?

Fewer than the brand count suggests. One pair on our list posts identical prices on virtually every runner they both quote, which is a single feed under two names. Two further pairs agree roughly nineteen times in twenty, which is not one feed but is not independent pricing either. The table on this page names all three and gives the exact figures.

Are exchanges included?

No. Exchanges charge commission on winnings instead of building a margin into the price, and spread firms are not quoting win odds at all. Including either would produce a book that looks impossibly tight.

Do your affiliate partners get a better position?

No. The order is whatever the data produced. The tightest book is not a partner, and the first firm that ever paid us sits in the bottom half of the table.