United StatesWhat Is Arbitrage Betting? US Guide
Arbitrage betting covers every possible outcome of the same market at prices that produce a modeled return regardless of the result.
The math only holds when every wager is accepted at the entered price and each sportsbook uses matching settlement rules.
Reviewed by WagerWise · Updated September 18, 2026
Cover Every Listed Outcome
Arbitrage betting, often shortened to arbing, uses price differences between sportsbooks. The bettor places a wager on every possible outcome of one market so the calculated payout is higher than the combined stakes.
The opportunity exists when the implied probabilities of the best available prices add up to less than 100%. It is a pricing condition, not a prediction about which team or player will win.
- Arbitrage bet
- A coordinated set of wagers covering every possible outcome of the same market.
- Implied probability
- The chance represented by a sportsbook price after converting the odds.
- Arbitrage percentage
- The sum of the implied probabilities across the selected outcomes. A total below 100% indicates a theoretical arb.
- Stake split
- The amount placed on each outcome so the modeled payout stays as even as possible.
The Math With American Odds
Convert each American price to implied probability, then add the results. Positive odds use 100 ÷ (odds + 100). Negative odds use the absolute price ÷ (absolute price + 100).
Two prices of +110 each imply 47.62%. Together they total 95.24%, which is below 100% and creates a theoretical arbitrage opportunity.
Arbitrage percentage = implied probability A + implied probability B + any other outcomesA Two-Way US Sportsbook Example
FanDuel lists one side of a matching two-way market at +110. DraftKings lists the opposite side at +110. A $100 total stake is split evenly because the prices match.
The $5 is not certain until both wagers are accepted and settled. A price move, rejected stake, voided wager or market mismatch can remove the calculated return.
| Measure | Calculation | Result |
|---|---|---|
| Side A implied chance | 100 ÷ (110 + 100) | 47.62% |
| Side B implied chance | 100 ÷ (110 + 100) | 47.62% |
| Combined probability | 47.62% + 47.62% | 95.24% |
| Stake split | $100 ÷ 2 | $50 each |
| Payout either way | $50 × 2.10 | $105 |
| Modeled return | $105 − $100 | $5 |
How to Place an Arbitrage Bet
Speed matters, but matching the market matters more. A fast bet on the wrong line is not an arb.
- Match the exact wagerConfirm the event, period, selection, line and settlement rules. Lakers -3.5 is not Lakers -4, and a full-game total is not a first-half total.
- Check every current priceOpen each sportsbook and confirm the displayed American odds are still available for the stake you plan to place.
- Calculate the stake splitUse the total bankroll and every accepted price. Do not round so heavily that the smaller payout falls below the total stake.
- Place the harder leg firstThe lower-limit or faster-moving wager is usually more likely to change. Recalculate immediately if the accepted price differs.
- Verify and record both betsCheck the bet slips, accepted odds, stakes and potential payouts. Save the record until every leg settles.
Live betting increases timing and acceptance risk. Pregame markets are easier to verify when you are learning the process.
US Markets That Must Match
Arbitrage can appear in several market types. The labels may look similar while the actual wagers differ.
| Market | What must match | Common mismatch |
|---|---|---|
| Moneyline | Same event, period and draw treatment | One sportsbook includes overtime while another does not |
| Point spread | Same team and exact spread | -3 is compared with -3.5 |
| Game total | Same period and exact over/under line | Over 47.5 is compared with Under 48 |
| Player prop | Same player, statistic, line and participation rule | Void rules differ when the player does not start |
| Three-way moneyline | Home, draw and away for the same regulation period | A two-way market that includes overtime is mixed in |
Different market rules can create the appearance of an arb even when the outcomes do not fully cover each other.
The Math Is Clean. Execution Is Not.
Arbitrage reduces outcome risk only when the entire position is placed and honored as calculated. These are the failure points that matter.
- Odds movementA sportsbook can change the price before the wager is accepted. The original stake split may no longer cover the total outlay.
- Stake limitsOne sportsbook may accept less than the requested amount, leaving the other side overexposed.
- Rejected or delayed betsAn accepted first leg can remain open while the second wager is reviewed or rejected.
- Different settlement rulesOvertime, pushes, dead heats, player participation and void rules can change the set of covered outcomes.
- Account restrictionsSportsbooks may reduce limits or restrict accounts under their terms.
- Access and fundingState availability, deposit timing, withdrawals and identity checks affect whether the full position can be placed and settled.
Is Arbitrage Betting Legal in the US?
Arbitrage is a way to combine sportsbook wagers, not a separate type of bet. Sports betting laws, operator availability and permitted markets vary by state.
Use sportsbooks authorized where you are physically located, confirm that you meet the age requirement and follow each operator's terms. WagerWise does not make a sportsbook legal or available in a state.
Check WagerWise US sportsbook coverage by state
Get confidential help from the National Council on Problem Gambling
General information only, not legal advice. Rules and sportsbook terms can change.
Find the Price Gap Before It Moves
Manual comparison works for one game. It does not scale across sportsbook markets that keep repricing.
WagerWise compares supported US sportsbook prices, identifies matching outcomes and calculates the proposed stake split. Confirm every market and price at the sportsbook before placing a wager.
See current US arbitrage bets
Straight Answers
What is arbitrage betting?
Arbitrage betting covers every possible outcome of the same market across different sportsbooks at prices that produce a modeled payout above the combined stakes.
Does arbitrage betting guarantee a profit?
The calculation produces a return only if every wager is accepted at the entered price and settles under matching rules. Price movement, rejected stakes, voids and market mismatches can remove the return.
Can I calculate an arbitrage bet with American odds?
Yes. Convert each American price to implied probability, add the probabilities and calculate the stake split. A combined probability below 100% indicates a theoretical arbitrage opportunity.
Is arbitrage betting legal in the US?
Sports betting laws and operator availability vary by state. Use sportsbooks authorized where you are located and follow each operator's terms.
Which US sportsbook markets can produce arbitrage?
Arbitrage can appear in matching moneylines, point spreads, game totals, player props and three-way markets. The event, period, line and settlement rules must match.
What tools do I need for arbitrage betting?
An arbitrage finder compares current prices. An arbitrage calculator converts those prices into a stake split and modeled payout. You still need to verify every wager at the sportsbook.
Check the Market. Then Check the Math.
Run the prices through the free calculator. When you are ready to scan supported US sportsbooks, open the WagerWise arbitrage board.