"Just back the favourite" is the oldest advice in betting. We tested it properly — every single favourite in Britain and Ireland over 11 years, settled at starting price. The verdict: backing them all loses you 7.4p in every pound. Favourites win plenty of races. They do not win at a profit.
A 34% strike rate sounds healthy, and it is — roughly one favourite in three obliges. The problem is price. To break even at an average SP of 3.10 you would need to win about 37% of the time, and the market sets the favourite's odds precisely so that you don't. That 7.4-point gap is the bookmakers' margin, and it is remarkably stable across the whole decade.
Splitting favourites by their own odds shows the pattern clearly: the shorter the favourite, the smaller the loss — but every band still loses.
| Favourite's SP | Races | Strike rate | Level-stake ROI |
|---|---|---|---|
| Odds-on (under 2.0) | 22,906 | 59.7% | −4.9% |
| 2.0 – 2.9 | 45,599 | 38.4% | −6.9% |
| 3.0 – 4.9 | 61,393 | 25.3% | −8.6% |
| 5.0+ | 11,597 | 16.4% | −10.2% |
Even odds-on favourites — winning almost 60% of the time — return −4.9%. The longer a favourite's price, the more the market is telling you it isn't confident, and the worse the blind bet performs.
This isn't an argument against favourites — it's an argument against backing them blindly. The favourite is the market's opinion, and the market is efficient: its price already contains the public form, the going, the draw and the connections. To make betting pay you cannot simply follow the favourite — you have to find the times the market has the price wrong.
That is the entire point of what we do. Our model scores every runner against a decade of data and flags the ones whose real chance differs from their price — sometimes that's the favourite, often it isn't. Following the crowd costs 7.4%; the edge is in knowing when the crowd is wrong.
Sample: every race with a recorded starting price and result, Britain & Ireland, 2015–2026 (141,337 races). Favourite = shortest SP in the race; level 1-point stakes; returns at SP.
Data: official UK & Irish results, 2015–2026. Historical patterns are not a guarantee of future results. 18+ · BeGambleAware.