Arbitrage Betting

Placing bets on every outcome across different bookmakers whose combined implied probability is under 100%, locking in a small guaranteed profit whatever the result.

Definition

Arbitrage exploits price differences between bookmakers: when the best available odds for each outcome imply a total probability below 100%, staking each outcome in the right proportion guarantees a profit regardless of the result, and the edge is the gap below 100%. In practice arbitrage is constrained by low stake limits, odds that move or disappear before all legs are placed, and bookmakers restricting or closing accounts that arb consistently, so it is far harder and less scalable than the maths suggests.

Worked example

Book 1 prices Team A at 2.10 and Book 2 prices Team B at 2.10 in a two-way market. Implied probabilities are 47.62% + 47.62% = 95.24%, a 4.76% arb. Staking $500 on each returns $1,050 whichever team wins, a guaranteed $50 profit on $1,000 staked.

Why it matters

Learners see how implied probabilities across books reveal mispricing, while in reality account limits and line moves mean guaranteed profit is rarely repeatable at scale.

Related

Note: Real arbitrage opportunities are typically well under 2% and short-lived; the 4.76% figure is illustrative.