What is Arbitrage Betting?
Guarantee profits by betting all outcomes across different sportsbooks. Learn how arbing works and what you need to know.
Quick Answer
Arbitrage betting (or "arbing") exploits pricing differences between sportsbooks to lock in guaranteed profits. When odds at different books are far enough apart, you can bet on all outcomes and profit no matter what happens. It's legal but sportsbooks actively work to limit arbers.
How Arbitrage Betting Works
Arbitrage opportunities exist when the combined implied probability of all outcomes falls below 100%. In a normal market, sportsbooks ensure the implied probabilities add up to more than 100%—that's their edge (the vig). But when different books have different opinions, gaps can appear.
Example: 2-Way Arbitrage Opportunity
Lakers vs. Celtics — Moneyline Market
Sportsbook A
Lakers +150
Implied probability: 40.0%
Sportsbook B
Celtics -130
Implied probability: 56.5%
Combined implied probability: 40.0% + 56.5% = 96.5%
Since this is below 100%, an arbitrage opportunity exists!
Bet Sizing ($1,000 total bankroll):
- Bet $414.51 on Lakers +150 at Sportsbook A
If Lakers win: $414.51 × 2.50 = $1,036.28
- Bet $585.49 on Celtics -130 at Sportsbook B
If Celtics win: $585.49 × 1.77 = $1,036.32
Guaranteed profit: ~$36 (3.6% return) regardless of outcome
The Math Behind Arbitrage
To check if an arbitrage opportunity exists, convert odds to implied probability and add them up:
Implied Probability Formulas:
Positive odds (+150): 100 ÷ (150 + 100) = 0.400 = 40.0%
Negative odds (-130): 130 ÷ (130 + 100) = 0.565 = 56.5%
If sum of implied probabilities < 100% → Arbitrage exists
The profit percentage equals: (100% - combined implied probability). If the combined probability is 96.5%, your guaranteed profit is 3.5% of your total stake.
Types of Arbitrage Opportunities
Two-Way Arbs
Moneylines with two outcomes (Team A vs Team B). Most common and easiest to find. Requires betting one side at each of two sportsbooks.
Three-Way Arbs
Markets with three outcomes (Win/Draw/Lose) like soccer or hockey regulation. Harder to find but can offer larger profit margins.
Middle/Middling
Betting both sides of a spread when there's a gap. You guarantee a small loss but have a chance to win both bets if the final lands in the "middle."
Realistic Expectations
| Factor | Reality |
|---|---|
| Typical profit per arb | 1-3% (larger arbs close quickly) |
| Capital needed | $5,000-$20,000+ across 5-10 sportsbooks |
| Time commitment | High—arbs disappear in minutes |
| Account longevity | 3-6 months before limits at most books |
| Annual ROI (active arbing) | 5-15% of deployed capital |
Risks and Challenges
Account Limitations
Sportsbooks aggressively limit arbers. You may be restricted to $5 maximum bets or have your account closed entirely. Sharp books limit fastest; soft books last longer.
Line Movement Risk
If one side of your arb gets placed but the other line moves before you bet, you're stuck with a one-sided bet. Speed is critical.
Bet Cancellations
Sportsbooks can void bets if they detect a line error ("palpable error"). If one side gets voided, you're left exposed on the other.
Capital Requirements
You need funds spread across many sportsbooks. Money tied up in pending bets or slow withdrawals limits how many arbs you can execute.
Arbitrage vs. +EV Betting
| Aspect | Arbitrage Betting | +EV Betting |
|---|---|---|
| Profit model | Guaranteed per bet | Expected over many bets |
| Risk per bet | Zero (if executed properly) | Can lose individual bets |
| Capital needs | High (both sides every bet) | Lower (one side per bet) |
| Accounts needed | Many (10+) | Fewer (4-6 can work) |
| Detection risk | Higher (obvious pattern) | Lower (looks more normal) |
| Variance | None | Short-term swings |
Why We Focus on +EV Betting
At +EV Bets, we help you find positive expected value opportunities rather than pure arbitrage. +EV betting is more sustainable long-term, requires less capital, and accounts last longer. While you'll experience variance, the math works in your favor over time.
Tips If You Try Arbitrage
1
Round bet amounts naturally
Bet $50 or $100, not $47.23. Odd amounts scream "arber" to sportsbooks.
2
Place some "normal" bets too
Mix in regular bets on favorites or popular teams to mask arbing activity.
3
Act fast—arbs close quickly
Have accounts funded and ready. Seconds matter when lines are moving.
4
Have a backup plan for limits
Accounts will eventually get limited. Plan for transitioning to +EV betting.
Frequently Asked Questions
What is arbitrage betting?
Arbitrage betting (or "arbing") is a strategy where you bet on all possible outcomes of an event at different sportsbooks to guarantee a profit regardless of the result. It exploits pricing differences between bookmakers when their combined odds create a situation where you can cover all outcomes for less than the payout.
Is arbitrage betting legal?
Yes, arbitrage betting is legal. You're simply placing bets at different sportsbooks. However, sportsbooks don't like arbers and may limit or ban accounts they suspect of exclusively arbing. It's not illegal, but it can get you restricted.
How much can you make from arbitrage betting?
Individual arbitrage opportunities typically yield 1-5% profit per event. The challenge is finding opportunities, having funds across multiple sportsbooks, and placing bets before lines move. Realistic annual returns depend on how much capital you can deploy and how many arbs you find.
How do sportsbooks feel about arbitrage bettors?
Sportsbooks actively discourage arbitrage betting. They use sophisticated tools to detect arbing patterns and will limit bet sizes or close accounts. Signs that flag accounts include: betting only on +EV/arb lines, strange bet amounts (like $47.23), and consistently betting right before line moves.
What's the difference between arbitrage and +EV betting?
Arbitrage guarantees a profit on every bet by covering all outcomes. +EV (positive expected value) betting identifies bets that are profitable over time but may lose individual bets. Arbing requires more capital (betting all sides) while +EV betting requires fewer accounts but more variance tolerance.