Guide · 6 min read
Making money from sports betting: what works mathematically and what doesn’t
Most people who bet on sports lose money over time, and that is not bad luck: it is built into the prices. A few methods rely on maths instead of opinions. This guide ranks every common route by expected value, swings, capital, time and the risk of being limited, so you can judge each one before you spend money on it.
Updated 22 October 2026
Contents
Why most bettors lose: the margin
A bookmaker never offers fair odds. Take a match where both sides have a 50% chance. Fair odds would be 2.00 on each side. A typical bookmaker offers 1.91 on each instead. The implied probabilities add up to 1/1.91 + 1/1.91 ≈ 104.7%. The extra 4.7% is the margin, also called overround or vig.
Now bet €10 on 100 such matches. On average you win 50 of them and collect 50 × €19.10 = €955. You staked €1,000, so you are €45 down, 4.5% of your stakes, without making a single bad choice. Good picks can offset that, but the margin is charged on every bet, whoever you back. More in bookmaker margin explained.
Research points the same way. Bookmaker prices are good forecasts of results (Forrest, Goddard and Simmons 2005), and bookmakers deal with customers who beat them by restricting their stakes rather than by changing their prices (Levitt 2004; Kaunitz, Zhong and Kreiner 2017). See can you win at sports betting long-term?
Every route compared
The table ranks the common approaches on the same five criteria. "Expected value" means what you should get back on average per euro staked over many bets, before your own mistakes. As of October 2026.
| Route | Expected value | Swings | Capital | Time | Limit risk |
|---|---|---|---|---|---|
| Gut feeling, favourite teams | Negative: you pay the margin | High | Any | Low | Low |
| Paid tips and tipsters | Usually negative after the fee; records are hard to verify | High | Any | Low | Low to medium |
| Accumulators | More negative: margins multiply | Very high | Small | Low | Low |
| Staking systems (martingale and similar) | Negative: a system doesn’t change the odds | Rare, very large losses | Grows fast | Medium | Low |
| Value betting | Positive if your price estimates are right | High | Medium | Medium | High |
| Matched betting (bonuses) | Positive per offer, while offers last | Low | Small to medium | Medium | Medium (bonus bans) |
| Sure bets (arbitrage) | Small and positive per bet, if every leg stands | Low per bet; voids and moved prices cause losses | Medium, spread over several accounts | Medium to high | High |
| Trading on betting exchanges | Depends on skill; commission on winnings | Medium to high | Medium | High | Low, but few exchanges are available |
The first four rows are what most people do. The last four are where maths-based approaches live, and they fail in different ways:
- Accumulators multiply margins: five legs at a 95% payout rate each give 0.95⁵ ≈ 77% for the whole bet, so about €23 of every €100 staked is expected to stay with the bookmaker.
- Staking systems change how much you bet, not your chances. With a martingale (double after each loss) starting at €10, seven losses in a row cost €1,270 and the next bet needs €1,280, all to win €10. See martingale betting.
- Value betting scales best among the maths-based methods but swings a lot: you can be behind for months with a real edge. See value betting vs arbitrage.
- Matched betting uses sign-up and reload bonuses. Each offer can be worked out in advance, but offers run out and bonus terms are strict. See matched betting.
- Sure bets cover every outcome at different bookmakers, so the payout is about the same whatever happens, if every leg is accepted at the shown odds and stands. The margin per bet is small, usually 0.5–2%, many below 1%. See sure betting explained.
A longer side-by-side of these methods is in betting strategies compared.
A sure bet in numbers
A tennis match. Bookmaker A offers 2.06 on player 1, bookmaker B offers 2.00 on player 2. Add the implied probabilities: 1/2.06 + 1/2.00 = 0.4854 + 0.5000 = 0.9854. That is below 1, so the prices leave a gap of about 1.5%.
With €200 in total you stake €98.52 on player 1 at A and €101.48 on player 2 at B. If player 1 wins: €98.52 × 2.06 = €202.95. If player 2 wins: €101.48 × 2.00 = €202.96. Either way about €2.95 more than the €200 staked.
That is the whole method: small amounts, many times, with no opinion about who wins. The example also shows the weak points. If bookmaker B drops its price before you place the second leg, or voids the bet, the first leg becomes an ordinary bet that can lose. That is why we never call sure bets risk-free. See the risks of arbitrage betting.
What is realistic
We don’t publish headline earnings, because they would mislead. What we can show is how the numbers behave:
- Results scale with stakes. A 1% realised margin on €10,000 of stakes in a month is about €100 before costs, if every leg stands.
- What would €1,000 a month take? At a 1% average margin, about €100,000 in stakes a month: roughly 167 sure bets of €600, more than five a day. Most people never get there, because bookmakers limit winning accounts. Use the calculator with your own numbers.
- Over time, limits shrink what each account accepts. The honest framing is a side project with a ceiling, not a job. See arbitrage betting as a side income.
Risks to know first
- No method guarantees a profit. Results vary and can be negative.
- Bookmakers limit or close winning accounts. That is legal and in their terms. See bookmaker limits.
- Your money sits at several bookmakers until bets settle, and withdrawals take days.
- Bookmakers can void bets placed on obvious price errors.
- 18+ only. Betting is never a solution to money problems. Only use money you can do without, never rent, bills or borrowed money.
Where ArbVantage fits
ArbVantage is software that finds price differences between bookmakers and works out your stakes. It shows sure bets (including free-bet conversion) and middles; value bets are coming soon. We do the maths; you decide every bet. It is built for beginners, in German, Slovak, English and Spanish, with the bookmakers people use in Austria and Slovakia. If sure bets sound like your route, start with how sure betting works.
Frequently asked questions
Is it possible to make money from sports betting?
Some people do, mostly with maths-based methods such as sure bets, matched betting or value betting, and usually for a limited time before their accounts are limited. Most bettors lose over time because of the bookmaker’s margin. Nothing guarantees a profit.
Which betting method has the smallest swings?
Per bet, sure bets and matched betting swing the least, because the outcomes are covered. They are not risk-free: odds can move before the second leg, bets can be voided, and mistakes in stakes cost money.
Do betting systems like the martingale work?
No. A staking system changes how much you bet, not the probability of winning. It turns many small wins into rare but large losses, and the bookmaker’s margin still applies to every bet.
How much money do I need to start with sure bets?
Sure betting needs money at two or more bookmakers at the same time, so the amount is spread over several accounts. Our starting bankroll guide works through €500, €2,000 and €5,000. Only use money you can do without.
Sources
- Levitt, S. D. (2004): Why are gambling markets organised so differently from financial markets? The Economic Journal 114(495), 223–246
- Kaunitz, L., Zhong, S., Kreiner, J. (2017): Beating the bookies with their own numbers, and how the online sports betting market is rigged, arXiv:1710.02824
- Forrest, D., Goddard, J., Simmons, R. (2005): Odds-setters as forecasters: The case of English football. International Journal of Forecasting 21(3), 551–564
- RIS: Glücksspielgesetz (GSpG), § 1 definition of gambling (in German)
- ÚRHH: licensed gambling and betting websites in Slovakia (in Slovak)
- Spielsuchthilfe (Austria): counselling for gambling problems (in German)
As of October 2026, checked against the linked sources. Not legal, tax or betting advice.
Betting involves risk, even with sure bets: prices move, bets get voided and accounts get limited. Only use money you can do without. Our responsible gambling page lists free help.
Not betting advice. 18+. Betting involves risk. See our disclaimer.