The myth is tidy: everyone piles on the favourite, so the second favourite is the overlooked value bet. We tested it on 201,567 UK and Irish races. The myth does not survive contact with the data. Second favourites win about one race in five and lose you money at starting price, more money than backing the favourite would.
"Back the second favourite" is one of those pub-wisdom systems that sounds clever because it sounds contrarian. The logic goes: the crowd over-bets the jolly, which shortens its price and leaves value on the next one in the market. It is a nice story. We have a database of UK and Irish results back to 2010, so we ranked every runner in every race by its starting price and pulled out the second-shortest in each: 201,567 races with a clear second favourite. Here is what actually happens.
So the second favourite wins a fraction over one race in five, and the market has it priced about right, if anything slightly too short. Far from being the smart contrarian play, blindly backing the second favourite is a steady, predictable way to hand the bookmaker six pence in the pound.
The clearest way to see it is to line up the top three in the betting. Win rate drops as you go down the market, and so does the return, in a straight line. There is no hidden pocket of value waiting at rank two.
| Position in betting | Avg SP | Win rate | ROI at SP |
|---|---|---|---|
| Favourite | 3.19 | 35.9% | +0.5% |
| Second favourite | 4.86 | 20.9% | -6.2% |
| Third favourite | 7.17 | 14.0% | -10.3% |
The favourite is the only one of the three that even reaches break-even, and it only just does. Each step down the market costs you both a chunk of strike rate and a chunk of return. The crowd is not leaving value on the second favourite; the market has already done its job on every runner in the line-up.
Not in any way you can bet on. We split the second favourites by their own starting price to check whether a shorter or bigger-priced second favourite behaves differently. Every band loses, with one tiny exception that is noise rather than a signal.
| Second favourite's price | Races | Win rate | ROI at SP |
|---|---|---|---|
| 2/1 or shorter | 18,127 | 32.4% | -11.0% |
| Bigger than 2/1 to 4/1 | 119,171 | 22.0% | -9.5% |
| Bigger than 4/1 to 8/1 | 61,915 | 15.6% | -1.5% |
| Bigger than 8/1 | 2,354 | 13.4% | +71.5% |
Three of the four bands lose, and the shorter the second favourite the worse it is, exactly the pattern we found for favourites. That last row looks spectacular at +71%, but read the sample size: 2,354 races out of 201,567. A "second favourite bigger than 8/1" only happens in wide-open markets where almost anything can win, and a handful of long-priced winners drag the average up. It is small-sample variance, not a system. Stake into it expecting +71% and you will be disappointed.
Market rank is not an edge. Favourite, second favourite, third favourite: each is just a label for where the crowd has placed a runner, and the price already reflects that. Picking a horse because of its position in the betting, in either direction, is picking the market's opinion, and the market is, on average, right enough to keep your money.
An edge has to come from the gap between what a horse is genuinely worth and what it is being offered at. Sometimes that horse is the favourite, sometimes it is the second or third favourite, and most of the time the gap is not there at all and the race is best left alone. That is the part a "back the second favourite" rule can never tell you.
The Overlay is a free, data-driven UK and Irish racing model. It looks for the gap between a horse's true chance and its price, logs every selection before the off, and settles in public, win or lose. It is not a tipster, and it tells you when to sit a race out. Free value board, bet calculator and a play-money tracker.
Explore The OverlayRelated reading: Do favourites win in horse racing? and more racing data studies.
We used every race in our database from 1 Jan 2010 to 2 Jun 2026 that had a settled result. In each race we ranked the runners by starting price and took the second-shortest as the second favourite. Win rate is second-favourite wins divided by races. ROI is level-stakes return at starting price: stake 1 point on the second favourite in every race and measure profit or loss per point. The favourite and third-favourite figures are calculated the same way for comparison. Figures are historical and for information only.