Arbitrage Betting: How to Guarantee Profit from Odds Differences

Arbitrage betting (or "arbing") is a strategy where you bet on all possible outcomes of an event across different sportsbooks, guaranteeing a profit regardless of the result. It works because sportsbooks sometimes disagree enough on odds to create a risk-free opportunity.

How Arbitrage Opportunities Arise

An arb exists when the combined implied probability across the best odds for each outcome is less than 100%. For example, if DraftKings has Team A at +120 (45.5% implied) and FanDuel has Team B at +105 (48.8% implied), the total is 94.3% — well under 100%. That 5.7% gap is your guaranteed profit margin.

Calculating Arbitrage Stakes

To arb correctly, you need to calculate the right stake for each side so the payout is the same regardless of outcome. The formula: Stake on Side A = (Total Investment × Implied Probability of A) / Total Implied Probability. Tools like Open Edge EV's arbitrage scanner do this math automatically.

Realistic Expectations

Most arbitrage opportunities yield 1-5% returns. They appear frequently but close fast — often within minutes. Speed is essential. You also need significant bankroll across multiple books to make the absolute dollar returns worthwhile.

Risks and Considerations

While arbs are theoretically risk-free, practical risks exist: lines can move after you place one side but before you place the other (called "one-legging"), sportsbooks can void bets on palpable errors, and heavy arb activity can lead to account limitations. Many experienced bettors prefer +EV betting over pure arbing because it's more sustainable and harder for books to detect.