What is Arbitrage Betting?
Arbitrage betting (also called "surebetting" or "arbing") is a strategy where you place bets on all possible outcomes of an event across different bookmakers to guarantee a profit, regardless of the result.
It's the same concept as financial market arbitrage — profiting from price discrepancies between different places. Bookmakers set their own odds independently, and occasionally those odds don't align. When that happens, a window opens where covering all outcomes still produces a net profit.
Normal Situation
Bookmakers' odds are aligned — covering all outcomes costs more than you'd win back. The overround (vig) ensures the bookie always profits.
Arbitrage Opportunity
Two bookmakers have diverged on the same market. Covering both outcomes costs less than the guaranteed return — locking in profit.
How Arbitrage Works
Bookmakers set odds based on their own models and market activity. They adjust independently to balance their book — and sometimes they overcorrect in opposite directions, creating a gap.
| Outcome | Bookmaker | Odds | Implied % |
|---|---|---|---|
| Under 6.5 Points | Sportsbet | $2.75 | 36.36% |
| Over 6.5 Points | TABtouch | $1.98 | 50.51% |
Total implied probability: 86.87% — well under 100%.
Result: a guaranteed profit margin exists by covering both sides with the correct stake split.
When the combined implied probability of all outcomes adds up to less than 100%, an arbitrage opportunity exists. The lower the combined total, the larger the guaranteed profit margin.
How to Calculate Your Stakes
To lock in the profit, you need to split your total stake across both outcomes in the right proportion. The formula is simple.
Stake Formula (per side)
Stake = Total Budget × (1 ÷ Odds) ÷ (1÷OddsA + 1÷OddsB)
Using the example above: Under @ $2.75 (Sportsbet) and Over @ $1.98 (TABtouch)
Weight A = 1 ÷ 2.75 = 0.3636
Weight B = 1 ÷ 1.98 = 0.5051
Total weight = 0.3636 + 0.5051 = 0.8687
Stake A = $500 × (0.3636 ÷ 0.8687) = $209 on Under
Stake B = $500 × (0.5051 ÷ 0.8687) = $291 on Over
If Under wins: $209 × $2.75 = $574.75 returned
If Over wins: $291 × $1.98 = $576.18 returned
Either way, you profit ~$75 on a $500 outlay — roughly 15% guaranteed.
Key Terminology
Why Arbitrage Opportunities Exist
Bookmakers don't coordinate with each other. They each run their own models, respond to different betting flows, and adjust odds at different speeds. This creates gaps.
Independent Pricing Models
Each bookmaker builds their own odds based on different data, creating divergent prices on the same market.
Different Liability Exposure
If one bookie is taking heavy action on one side, they may shorten those odds — while another bookie hasn't moved yet.
Promotions & Boosted Odds
Bookmakers regularly boost odds for promotional reasons, often creating arb windows they're aware of but absorb as marketing cost.
Slow Market Updates
Smaller or niche markets (player props, minor sports) update less frequently, leaving price discrepancies open for longer.
Risks to Know
Arbitrage is one of the lowest-risk betting strategies, but it's not completely risk-free. These are the main things to watch for:
| Risk | What Can Happen |
|---|---|
| One side voids | If a bookmaker voids your bet but the other side settles, you're left with an unhedged position and potential loss. |
| Odds move before you place | If odds shift between finding the arb and placing both bets, the guaranteed profit may disappear or reverse. |
| Bet limits / rejection | Bookmakers may cap your stake or reject a bet — leaving you exposed on the other side. |
| Account restrictions | Consistent arbing is one of the fastest ways to get limited. Your accounts are the most valuable asset. |
Protecting Your Accounts
Your bookmaker accounts are your most important asset. A restricted account means no more arbs. Longevity is the goal — not squeezing maximum profit from a single account before it gets clipped.
- ✓Round stakes naturally — $210 not $209.30. Unusual decimals stand out to risk teams.
- ✓Mix in casual-looking bets alongside arbs — recreational bettors don't only place perfectly hedged plays.
- ✓Avoid consistently hitting niche prop markets with large amounts — these are closely monitored.
- ✓Withdraw profits gradually, not in one large chunk after a big win.
- ✓Know the settlement rules for each bookmaker — especially on player props, DNPs, and voids.
- ✓Keep max win amounts reasonable on smaller sports to avoid triggering manual reviews.
Execution Checklist
When an arbitrage opportunity comes up, move through this before placing:
- ✓Open both bookmaker apps — have them ready before you start.
- ✓Find the exact same market on both sides — double-check Over vs Under, same line, same player.
- ✓Confirm the odds are still at the levels that create the arb.
- ✓Calculate your stake split based on your total budget.
- ✓Round both stakes to the nearest $5 or $10.
- ✓Place both bets as quickly as possible — don't let one sit while you place the other.
- ✓Confirm both bets are accepted before walking away.
Final Reminders
- 01Speed is everything — arb windows close fast. Have your apps open and funded.
- 02Always place both legs. Never leave yourself exposed on one side.
- 03Protect your accounts — consistent aggressive arbing is the fastest way to get limited.
- 04Round your stakes — never use odd decimal amounts.
- 05Know the rules — voids, DNPs, and settlement differences across bookmakers matter.
- 06Think long-term — a healthy account placed over months beats a clipped account after one week.
Sports betting involves a high risk of losing money and is not suitable for everyone. This guide is for educational purposes only. Always gamble responsibly. If gambling is affecting you, call the National Gambling Helpline on 1800 858 858 (free, 24/7).