Hedge vs arbitrage: what's the difference?

People use "hedging" and "arbitrage" like they're the same thing. They share a mechanism (bet both sides) but they aren't the same move, and mixing them up leads to bad decisions.

Hedging: you already have a bet

A hedge starts with a position you already hold. The market moves, and you place an opposite bet to lock in a profit or cut your risk. You took a real position first; the hedge is a decision about it. We covered the mechanics in how to hedge a bet.

Arbitrage: you bet both sides at the start

An arbitrage ("arb") exists when two books disagree enough that backing every outcome costs less than the guaranteed payout. You place both bets at once and profit regardless of the result.

Example: Book 1 offers Team A at +110, Book 2 offers Team B at +110.

• Implied probabilities: 47.62% + 47.62% = 95.24%. Anything under 100% is an arb.
• Bet $100 on each side ($200 total). Whichever wins returns $210.
• Guaranteed profit: $10, a 5% return on $200, no matter who wins.

Side by side

• Starting point: a hedge follows a bet you already made; an arb is built from scratch.
• Profit: a hedge can lock a profit or just limit a loss; an arb is a guaranteed profit by design.
• Edge needed: a hedge has none (it's a risk decision); an arb needs a real price gap between books.
• Frequency: hedge chances come up naturally; arbs are rare, small and vanish fast.

The risks that aren't in the math

• Moving lines. If the first bet lands and the second line moves, you're stuck holding a one-sided bet.
• Voids and rule differences. If one book voids a bet and the other doesn't, your "guaranteed" profit turns into a one-way wager.
• Account limits. Many sportsbooks restrict accounts that arbitrage consistently.
• Small margins. A 1–3% edge only pays if you can size it meaningfully and repeat it.

Quick answers