Average margin by market type:
- Two-way (no draw): 4.8%
- Over / under: 6.4%
- Three-way (home / draw / away): 7.5%
- Player stats: 7.6%
So a standard football home / draw / away market costs about 2.7 points more than a tennis or NBA match bet, just because the draw adds a third outcome for the bookie to load.
In pounds: on £100 of otherwise fair bets, a 4.8% margin costs about £4.58 and a 7.5% margin about £6.98.
Check any match yourself: 1 divided by each decimal price, add them up, see how far past 100% it goes. Home 2.30, draw 3.30, away 3.10 = 43.5% + 30.3% + 32.3% = 106%, so a 6% margin.
Full tables by sport: https://betbetter.world/studies/state-of-the-vig-2026