Arbitrage, in plain words
Arbitrage betting, or arbing, means betting every outcome of one market at different sportsbooks, at prices that add up to less than 100% implied. Split the stake the right way and every outcome returns the same amount, which is more than the total you staked.
Arbs exist because books disagree and move at different speeds. One book is slow to react to news, or shades a price to attract action, and for a short time its number and another book's number leave a gap. The returns are small, usually a percent or two of the total stake, and the gaps close fast.
The math is exact, but the risks are not in the math. A price can move before your second bet is placed. A book can void a bet, cap your stake or limit an account that arbs often. Two brands owned by one company can share one price sheet and cancel a mismatch. Low risk is the honest description; no risk is not.
The idea, drawn
Worked example · illustration
+110 at one book, −105 at another
- Side A
- +110 (47.62%)
- Side B
- −105 (51.22%)
- Implied total
- 98.84%
- Locked return
- 1.18%
- The two prices imply 47.62% + 51.22% = 98.84%, under 100%.
- On $100, stake $48.18 on side A and $51.82 on side B.
- Either side returns $101.18, a profit of $1.18 whatever happens.
1.18% is locked only if both bets stand at these prices. Place the harder leg first.