Sure Bets (Arbitrage Betting): A Complete Explanation and Tips
- Sure betting covers all outcomes across bookies.
- Also referred to as Arbitrage Betting.
- Strategy aims to guarantee small profits.
- Dangers do exist, as it is not “risk-free”.
- Bookmakers dislike it and may ban accounts.
Richard Trenchard
Last updated 26 Nov 2025
Sometimes referred to as arbitrage betting, sure bets are a strategic method of betting in which a punter attempts to guarantee profits by wagering on all possible outcomes of one event across multiple bookmakers. This guide serves as an educational resource to teach readers about this strategy and explain why it has gained traction in the UK among bettors.
Table of contents
- 1.How Do Sure Bets Occur?
- 2.The Math Behind a Sure Bet: A Step-by-Step Example
- 3.The Serious Risks and Dangers of Sure Betting
- 4.Is Arbitrage Betting Legal?
- 5.Tools Used for Arbitrage Betting
How Do Sure Bets Occur?
Sure bets occur for the following reasons:
- Bookmakers set different odds as they compete with each other.
- Odds can differ due to delays, as a bookmaker may be slow to update odds offered.
- Bookmakers may hold different views, which can influence the odds they offer.
The Math Behind a Sure Bet: A Step-by-Step Example
To understand the math behind a sure bet, let’s take the following example:
- Betting on a tennis match between two players.
- One bookmaker provides odds of 2.10 for Player A to win.
- Another bookmaker provides odds of 2.05 for Player B to win.
In this scenario, bettors want to work out whether the sum of the inverse odds is less than 1. Using the example above:
- The formula used would be (1 / 2.10) + (1 / 2.05) = 0.476 + 0.488 = 0.964; a sure bet exists.
After the maths has been done regarding the odds, another calculation should be completed to determine the stakes. This should be done for both potential outcomes:
- Player A winning on a £100 stake would be: (£100 / 0.964) x (1 / 2.10) = £49.40.
- Player B winning: (£100 / 0.964) x (1 / 2.05) = £50.60.
These figures would then need to be used to calculate potential profit:
- Player A wins would return: (£49.40 x 2.10) – £100 = £3.74 profit.
- Player B wins returns: (£50.60 x 2.05) – £100 = £3.73 profit.
The Serious Risks and Dangers of Sure Betting
Sure betting can often be promoted as “risk-free betting,” however, it can still pose dangers to players who are inexperienced or irresponsible when using this strategy.
Potential dangers can include:
- Bet Cancellation (Palpable Errors) – Bookmakers can void bets if the odds offered were a “palpable error.” If this happens, a bet on another bookmaker may still be active, which could result in lost funds.
- Rapid Odds Changes – Odds can be changed very quickly, which can leave players vulnerable when switching between bookmakers to place a bet.
- Account Limitations & Closures – Accounts can be limited as they are regularly monitored for suspicious activities, including when placing sure bets. Frequent wins can highlight arbitrage betting taking place, even if returns are small.
- Differing Bookmaker Rules – Bookmaker rules can vary across different markets, potentially affecting bets that have been placed. For instance, one bookmaker may pay out when another refuses due to a specific event that occurs.
Is Arbitrage Betting Legal?
Yes, arbitrage betting is completely legal to engage in. However, it is strongly frowned upon by bookmakers. Many will limit or ban accounts if players are suspected of engaging in this strategy.
Tools Used for Arbitrage Betting
Bettors can use the internet to find tools that identify sure bets. Several platforms are available, as are online calculators and odds comparison tools. These platforms can help identify potential opportunities that players can capitalize on, such as highlighting major discrepancies between bookmakers and the odds set for a specific outcome.
However, they must do so at their own risk, as there is a possibility of being discovered and facing restrictions or bans.
FAQ
Can you really not lose with a sure bet?
It is still possible to lose when engaging in sure betting. It is not a “risk-free” approach, with many dangers existing that are beyond a player’s control.
Why do bookmakers dislike arbitrage betting?
Bookmakers frown heavily upon arbitrage betting because it threatens their profits. The approach is designed for bettors to make profits, which bookmakers are trying to limit.
How much can you make from sure bets?
Large profits cannot be expected when making sure bets, but small, frequent profits can be achieved. It will depend on the stake placed, but a common yield profit margin of between 1% and 5% is often returned.
Are sure bets more common on live (in-play) events?
Yes, sure bets are more common on live events. This is because odds can change quickly, increasing the potential for discrepancies between bookmakers.
What's the difference between a sure bet and a value bet?
Sure bets are designed for frequent, short-term profits by covering all betting outcomes. Value bets are where players only bet on the odds that are in their favour for higher, long-term profits.
Meet the Author
We're delighted to have Richard on board at Flashscore. Offering a wealth of experience, Rich used to be a national newspaper and sports journalist before focussing entirely on the igaming and sports betting spheres. That means he is able to combine super sharp editorial instinct and crisp content with a wealth of information, having worked with some of the biggest names in the business over the past decade. So, when you see Rich's name on an article, you know it's packed information you can trust. Whether it's information on a particular casino, betting terms explained, betting tips, the best betting sites around, or anything else, Rich has got your back.
