Guide · 7 min read
What is a good arbitrage percentage?
A 1.5% sure bet looks fine until a betting fee, a withdrawal charge or a failed second leg gets involved. Whether an arb is worth placing depends not on the percentage on screen but on what is left after every deduction. This guide works through it with real numbers, including Austria's 5% Wettgebühr.
Updated 22 October 2026
Contents
The short answer
There is no fixed minimum. A sure bet is worth placing when its expected net margin is positive and large enough to justify your time. The net margin is what remains after betting fees, payment costs, rounding and the average cost of legs that fail. If one leg sits with a bookmaker that passes the Austrian 5% betting fee on to you, a two-way arb needs roughly 2.7% gross just to break even.
Gross and net margin
The gross margin is the number a scanner shows. Add up 1 ÷ odds for every outcome to get a sum S. If S is below 1, you have a sure bet, and the margin is 1 ÷ S − 1.
Bookmaker A offers 2.06 on Player 1, Bookmaker B offers 2.00 on Player 2. S = 1/2.06 + 1/2.00 = 0.48544 + 0.50000 = 0.98544. Gross margin: 1 ÷ 0.98544 − 1 = 1.48%.
With €1,000 in total you stake €492.61 at A and €507.39 at B. Either result pays €1,014.78, so +€14.78, provided both bets are accepted at these odds and stand.
The net margin is what actually reaches your account. Some tools show 1 − S instead of 1 ÷ S − 1; for small margins the difference is tiny (1.46% instead of 1.48%), so just be consistent. The basics are in our guide to sure betting, and the stake split is worked out in the arbitrage calculator guide.
Deduction 1: betting fees passed on to you
Since 1 April 2025 Austria charges a 5% Wettgebühr on the stake. The bookmaker owes it. Most bookmakers absorb it, and then nothing changes for you. Some pass it on; in Austria, Interwetten deducts it from the payout (our information as of October 2026; always check the bet slip). Your effective odds there are then odds × 0.95. Germany has a separate 5.3% betting tax on stakes, which many operators also pass on.
Effective odds at A: 2.06 × 0.95 = 1.957. S = 1/1.957 + 1/2.00 = 0.51099 + 0.50000 = 1.01099, which is above 1. Re-split (€505.43 at A, €494.57 at B), every result pays €989.13: about −€10.87 whoever wins.
If you keep the original split, you make +€14.78 if Player 2 wins and lose €35.96 if Player 1 wins. The sure bet has turned into an ordinary bet with risk.
The fee cost 2.6 percentage points here. As a rule of thumb, if one leg of a two-way arb is with a bookmaker that deducts the fee from the payout, the gross margin has to exceed about 2.7% before anything is left. Our guide to the Austrian betting tax explains who passes it on and how to spot it on the slip.
Deduction 2: payment costs, currency and rounding
- Deposit and withdrawal fees. Some payment methods charge a fixed amount or a percentage per transaction. A €2.50 fee eats a sixth of a €14.78 arb. Spread such costs over your turnover: €10 of fees a month on €20,000 of stakes is 0.05 percentage points.
- Currency conversion. If an account runs in another currency, every exchange costs money. Euro accounts avoid it.
- Rounding. Odd stakes such as €492.61 stand out. Rounding to €493 and €507 cuts the worse result from €14.78 to €14.00, barely noticeable on €1,000. On €100 it matters more: €49 and €51 instead of €49.26 and €50.74 cut the worse result from €1.48 to €0.94. The smaller the stake, the more rounding costs in percentage terms.
The expected cost of failed legs
The quoted margin only holds if every leg is accepted at the quoted odds. In practice something regularly gets in the way: the price at B drops before you place the second bet, the bookmaker accepts only part of your stake, or it rejects the bet. You then cover at worse odds or leave the first bet open.
Your €492.61 at A at 2.06 is already placed. B now offers only 1.90. To pay the same on both outcomes you stake €534.09 at B. Total staked €1,026.70, payout €1,014.78: −€11.93 instead of +€14.78. The failure cost you about €26.70 against the plan.
If that happens on one arb in ten, it costs €2.67 per arb on average, and the expected margin falls from 1.48% to about 1.21%.
The formula behind it: expected cost = probability of failure × average loss per failure. You only know both numbers from your own records, so log every arb with the slip odds, the time and the outcome. Other things that can go wrong are covered in arbitrage betting risks and bookmaker limits.
Why 10% and more is usually an error
Real sure bets between reputable bookmakers are mostly between 0.5% and 3%. When a scanner shows 10%, 20% or more, the cause is almost always one of these:
- A palpable error. A bookmaker mistyped a price. Most terms allow bets at obviously wrong odds to be voided or settled at the correct price, which leaves your other leg unhedged.
- Different rules. One bookmaker settles after 90 minutes, the other including extra time; one treats a tennis retirement as a loss, the other voids the bet.
- The wrong line. Handicap −1.5 matched with −0.5, an Asian handicap with a European one, or a different match with a similar name.
- Stale data. One of the prices was pulled from the market long ago.
ArbVantage therefore first drops any bookmaker whose price deviates by more than 10% from the margin-free median of the others. Sure bets above 15% get a "check carefully" flag, are always listed after normal arbs and are hidden by the default maximum-margin filter (15%). Above 30% they are discarded. How to check a price against the market is explained in no-vig fair odds.
A rule of thumb with your own numbers
One line is enough for the decision:
expected net margin ≈ gross margin − fee effect − payment costs − rounding − (failure rate × loss per failure)
| Item | Example |
|---|---|
| Gross margin shown by the scanner | 1.80% |
| Betting fee (both bookmakers absorb it) | 0.00% |
| Payment costs spread over turnover | −0.05% |
| Rounding at €1,000 total stake | −0.08% |
| Failed legs: 8% × 2.5% loss | −0.20% |
| Expected net margin | ≈ 1.47% |
Put in your own values. If the net figure is clearly less than your time is worth, skip the arb. Also think about the accounts: every arb makes a limit at a soft bookmaker a little more likely, so small margins in markets that attract attention are often worse than the number suggests. How much money you need in total is covered in bankroll.
All figures are worked examples with the stated assumptions, not a forecast. Real results vary and can be negative: odds move, bets get voided and accounts get limited.
Frequently asked questions
Are 1% sure bets worth it?
They can be, if no betting fee is passed on, there are no payment fees and both legs are reliably accepted. On €1,000 in total, 1% is about €10 before any costs. A single passed-on betting fee or one failed second leg turns that into a loss.
Why does ArbVantage hide sure bets above 15% by default?
Because margins that high almost always point to an error: a palpable price error, different settlement rules, a mismatched line or stale data. They are kept with a "check carefully" flag and always listed after normal sure bets; you see them if you raise the maximum-margin filter. Above 30% they are discarded.
How does the Austrian betting fee affect a sure bet?
If the bookmaker absorbs the 5%, not at all. If it deducts it from the payout, its odds are effectively 5% lower, so 2.06 becomes 1.957. On a two-way sure bet that costs about 2.6 percentage points of margin, so the gross margin needs to be above roughly 2.7%.
What margin do real sure bets usually have?
Most genuine sure bets between reputable bookmakers sit between about 0.5% and 3%. Anything from about 8% should be checked very carefully, because it is usually an error rather than an opportunity.
Sources
- Unternehmensserviceportal (USP, Austria): Wettgebührenabrechnung
- RIS: Gebührengesetz 1957, § 33 TP 17 (betting fee)
- Germany: RennwLottG § 18: 5.3% rate; § 17: tax base (in German)
- Kaunitz, Zhong, Kreiner (2017): Beating the bookies with their own numbers, arXiv:1710.02824 (limits on winning accounts)
As of October 2026. Individual bookmakers' fee practice can change; your bet slip is what counts.
Betting involves risk, sure bets included: odds change, bets get voided and accounts get limited. Only bet money you can afford to lose. Our responsible gambling page lists free help.
Not betting, legal or tax advice. 18+. As of October 2026. See our disclaimer.