How Often Do Horse Racing Favourites Win? 27,250 UK & Irish Races
Across 27,250 UK and Irish races, favourites won almost exactly as often as their exchange SP said they would. That accuracy is why backing them blind still costs money.
My grandfather used to say the favourite is the one horse everybody has already done the homework on. Before I write any of my horse racing tips, I want to know whether that homework is any good. So I looked at every clear exchange SP favourite in 27,250 UK and Irish races and asked two plain questions: how often do they win, and does following them pay?
The headline answer is that favourites won 34.7% of the time against a 35.0% chance implied by their price. The market is remarkably well calibrated. Backing every one of them returned −0.4% before commission and −3.7% after it, so there is no edge in the favourite itself. Any edge has to come from judgement about which favourites to oppose.
Favourites win almost exactly as often as their price says
Each row pairs what the exchange SP implied with what the favourites actually delivered. The two dots barely separate anywhere on the scale. Favourites under 1.50 won 75.2% of 1,056 races against 75.8% implied, and those at 5.00+ won 17.5% against 17.3%. The median favourite went off at 3.15, which sits right in the thick of the chart.
The only band that looks soft is 1.50-1.99, where favourites won 55.1% against 56.8% implied, a shortfall of −1.7 points. At the other end, 4.00-4.99 favourites beat their price by +0.5 points. Both gaps sit inside or close to their 95% ranges, so I read them as hints rather than rules.
Implied probability = 1 / exchange SP. 95% ranges shown.
View the data: priced vs delivered
| Implied by exchange SP | Actually won | 95% range | |
|---|---|---|---|
| Under 1.50 (1,056 races) | 75.8% | 75.2% | ±2.6 |
| 1.50-1.99 (3,007 races) | 56.8% | 55.1% | ±1.8 |
| 2.00-2.49 (4,049 races) | 44.6% | 44.5% | ±1.5 |
| 2.50-2.99 (4,290 races) | 36.6% | 35.5% | ±1.4 |
| 3.00-3.49 (3,880 races) | 31.0% | 30.9% | ±1.5 |
| 3.50-3.99 (3,422 races) | 26.9% | 26.8% | ±1.5 |
| 4.00-4.99 (4,361 races) | 22.6% | 23.1% | ±1.3 |
| 5.00+ (3,185 races) | 17.3% | 17.5% | ±1.3 |
For a bettor, this means the price is already an honest summary of a favourite's chance. If you back a short-priced horse, you need a specific reason from the form, the going or the pace to think the market has it wrong. A general feeling that favourites are good things is not a reason.
Longer-priced favourites finish unplaced more often than they win
This is the chart I would pin above my desk. In races with a place market paying two or more places, favourites won 34.7%, placed without winning 30.1% and finished out of the places 35.2%. Overall, a favourite is slightly more likely to be unplaced than to win.
The split changes sharply with price. Favourites under 1.50 were unplaced only 6.2% of the time, but those at 5.00+ missed the places 54.2% of the time. A weak favourite in a competitive handicap is often just the best of a weak bunch in an open race.
Placed = paid in the betting exchange place market for that race (place terms vary with field size).
View the data: how favourites finish
| Won | Placed, not won | Unplaced | |
|---|---|---|---|
| Under 1.50 | 75.2% | 18.6% | 6.2% |
| 1.50-1.99 | 55.1% | 28.7% | 16.2% |
| 2.00-2.49 | 44.5% | 31.6% | 23.9% |
| 2.50-2.99 | 35.6% | 31.5% | 33.0% |
| 3.00-3.49 | 30.9% | 31.8% | 37.4% |
| 3.50-3.99 | 26.8% | 30.8% | 42.4% |
| 4.00-4.99 | 23.1% | 30.6% | 46.3% |
| 5.00+ | 17.5% | 28.3% | 54.2% |
This is where my each-way instincts come from. When the favourite is long and fragile, the places are shared around the field. A well-drawn horse with the right trip and a sensible pace setup can carry real place value in that kind of race.
Blind favourite backing loses once commission comes off
Here are the flat-stake returns by band, before and after 5% commission on winnings. Before commission, the total is close to break-even at −0.4%. After commission, every single band is in the red. The best was 4.00-4.99 at −1.8% after commission, even though it showed 2.2% before, and the worst was 2.50-2.99 at −5.6%.
One caveat matters more than the rest. Exchange SP is only known after the off, so these figures describe what an exchange SP backer received, not a price anyone could have locked in beforehand. Returns this close to zero can also be produced by chance alone, so I would not build a system on the slightly better bands.
Historical flat-stake returns, not a forecast.
View the data: backing every favourite at exchange sp
| Gross | After 5% commission | |
|---|---|---|
| Under 1.50 | −0.8% | −2.0% |
| 1.50-1.99 | −3.1% | −5.2% |
| 2.00-2.49 | −0.4% | −3.2% |
| 2.50-2.99 | −2.5% | −5.6% |
| 3.00-3.49 | −0.3% | −3.8% |
| 3.50-3.99 | −0.4% | −4.1% |
| 4.00-4.99 | +2.2% | −1.8% |
| 5.00+ | +1.4% | −2.8% |
| All favourites | −0.4% | −3.7% |
My conclusion is simple. When a market is this efficient, commission alone is enough to make blind backing a losing habit. Profit has to come from selection, not from the label.
Britain and Ireland favourites diverge slightly on strike rate
The table splits the picture by country and by year. In Great Britain, favourites won 35.3% of 21,040 races against 35.4% implied, a return of −3.1% after commission. In Ireland, they won 32.7% of 6,210 races against 33.6% implied, and the return fell to −5.5%.
The yearly rows are steadier than I expected: 34.0% in 2024, 34.8% in 2025 and 35.3% in January-August 2026. The last of those is a partial year, so I treat it lightly. The Irish gap is the one I will keep watching, because slightly weaker favourites are exactly where I want to look for opposition.
| Split | Races | Implied | Won | Gap (pts) | Return after comm. |
|---|---|---|---|---|---|
| Great Britain | 21,040 | 35.4% | 35.3% | −0.2 | −3.1% |
| Ireland | 6,210 | 33.6% | 32.7% | −0.9 | −5.5% |
| 2024 | 7,580 | 34.2% | 34.0% | −0.3 | −3.6% |
| 2025 | 12,139 | 35.2% | 34.8% | −0.4 | −4.2% |
| 2026 (Jan-Aug) | 7,531 | 35.6% | 35.3% | −0.3 | −3.0% |
What I take from this
- Respect the price. Favourites won 34.7% against 35.0% implied, so the market's view of a favourite is usually right. Opposing one needs a concrete form reason.
- Weak favourites, open places. Favourites at 5.00+ were unplaced 54.2% of the time. Those races are where I hunt each-way and place value.
- Commission decides it. A −0.4% gross return became −3.7% after commission. Following favourites blindly is a slow leak, not a strategy.
Questions from readers
What percentage of horse racing favourites win in the UK and Ireland?
Across 27,250 UK and Irish races, the exchange SP favourite won 34.7% of the time. That is almost exactly the 35.0% chance their prices implied.
Is it profitable to back every favourite?
Not on this evidence. Backing every favourite at exchange SP returned −0.4% before commission and −3.7% after 5% commission on winnings.
How often do favourites finish out of the places?
In races with a place market paying two or more places, favourites were unplaced 35.2% of the time. The figure rose to 54.2% for favourites at 5.00+.
I'm Indira Rao, based in Brisbane, and I write the horse racing tips at htftpredictions.com — reading form, going and pace rather than chasing the favourite.
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