Why That 8.00 Longshot Often Loses You More Than a 1.50 Favourite
Longshot bets at big odds often look tempting but usually mean overpaying for unlikely outcomes. Meanwhile, favourites closer to 1.50 odds tend to have fairer prices backed by real win chances — here’s why that matters for your wallet.
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Picking an 8.00 shot looks thrilling but carries a hidden cost
Imagine you back a horse at odds of 8.00 (7/1) with a £10 stake. The implied probability says the horse has a 12.5% chance (1 / 8.00). But historical data often shows longshots winning far less than that — say only 5 to 7%. This means the bookmaker’s price is too generous on the surface, but it’s actually worse value than you'd guess.
Contrast that with a 1.50 favourite, where the implied probability is 66.7% (1 / 1.50). Studies show favourites win close to their implied odds in many markets. These favourites aren’t giveaways but often represent fair or even undervalued chances.
Backing the 8.00 shot for the thrill is common among recreational bettors, but the final effect usually erodes bankrolls because these bets systematically lose more in the long run.
The favourite–longshot bias is more than a guess — it's proven by numbers
Across thousands of races or matches, longshots tend to win less frequently than their odds suggest, while favourites hover around or sometimes outperform implied probabilities. This pattern is called the favourite–longshot bias.
Let’s compare an actual win rate vs. implied probability for two examples:
| Bet Type | Odds | Implied Probability (1 / Odds) | Actual Win Rate | Overpricing Indicator |
|---|---|---|---|---|
| Favourite | 1.50 | 66.7% | 63–67% | Fair price |
| Longshot | 8.00 | 12.5% | 5–7% | Overpriced |
The "overpricing indicator" signals where the bookmaker’s price includes extra margin hidden by bettor demand. Favourite odds are tighter because professionals and sharp money focus there. Longshots get inflated by casual bettors chasing big wins.
Why do bettors pay extra for longshots? The lottery-ticket effect
Most casual bettors enjoy the excitement of backing an unlikely winner. It’s fun to imagine turning £10 into £80 on one bet. This desire inflates demand for longshots, pushing odds down less than justified or even shortening prices right before matches.
There’s no shame in chasing these thrills, but realize the bookmaker exploits this behavior. Essentially, bettors pay a premium for the "lottery ticket" experience, eroding expected value.
Where the favourite–longshot bias hits hardest
The bias isn’t uniform across all markets:
- Outright markets: Big-field events like Grand National or World Cup winner markets highlight the bias. Long odds are common, but winners come from a small subset of contenders more often than odds imply.
- Big fields: Races or matches with 15+ competitors exaggerate the mispricing, since the general quality gap is wide but market attention uneven.
- Accumulator legs: Individual longshots within multi-leg bets are often priced generously but accumulate risk rapidly. A single low-probability leg kills the whole bet more often than the odds suggest.
Bettors who blindly lump longshots into their bets here without extra caution tend to bleed units despite occasional big wins.
A numeric example: Why backing a 1.50 favourite beats a lucky 8.00 shot long-term
Suppose you bet £100 on each type over 100 bets.
- At 1.50 odds, you expect wins about 66.7 times. Let’s take a real win rate of 65% for a conservative estimate.
- At 8.00 odds, the implied probability is 12.5%, but the real win rate is closer to 6%.
Calculate expected returns:
| Bet Type | Bets | Win Rate | Wins | Losses | Return per Win | Total Return | Profit/Loss |
|---|---|---|---|---|---|---|---|
| Favourite | 100 | 65% | 65 | 35 | £150 | £9,750 | £750 |
| Longshot | 100 | 6% | 6 | 94 | £800 | £4,800 | -£5,200 |
Breakdown:
- Favourite bets: 65 wins × £150 = £9,750. Losses: 35 × £100 = £3,500. Net profit = £9,750 - £10,000 (stakes) = -£250 (corrected below)
Actually the stake is £100 per bet, total £10,000. Wins payout = 65 × 1.5 × £100 = £9,750 (including stake) Net profit = £9,750 - £10,000 = -£250 — but losses also 35 × £100 = £3,500 means total stake calculation must not double count losses.
Correction:
- Total stake = £10,000
- Total return from wins = 65 × £150 = £9,750
- Losses lose stake: 35 × £100 = £3,500
Wait, losses already accounted in total stake, so net is £9,750 - £10,000 = -£250, i.e. slight loss. Suppose actual win rate slightly higher (66.7%), then
66.7 wins × £150 = £10,005 return, so almost break even.
For longshots:
- Wins return: 6 × £800 = £4,800
- Total staked: £10,000
- Net loss: £10,000 - £4,800 = £5,200 loss
Conclusion: despite huge payouts, the low win rate kills you.
What a sharp bettor does: treat long odds with respect, demand bigger edges
The takeaway isn’t "always back favourites" — sometimes 8.00 shots pop and hit, and big prices can be worth it. But you shouldn’t bet on them expecting bookmaker generosity.
A disciplined bettor:
- Seeks evidence longshots have a real probability edge beyond inflated market prices.
- Requires bigger margins or deeper confidence to risk funds on long odds.
- Prefers fair or undervalued favourite bets when edges are hard to find on longshots.
Don’t forget: backing multiple favourites at 1.50 odds profitably over hundreds of bets is easier than chasing one or two big 8.00 wins that vanish in a hail of small losses.
What should you do next?
When you see a price like 8.00, don’t buy excitement without scrutiny. Ask yourself:
- Is there real logic or data supporting this implied probability, or is the market inflated by casual money?
- Am I getting an edge sufficient to justify risking my stake?
Try tracking your own bets across favourites and longshots, calculating simple win rates and returns over time. You might discover your favourite bets keep you afloat while longshots drain your bankroll.
Ultimately, bet with your head. Betting excitement is fine, but expect to pay for it — and adjust your staking and expectations accordingly.