Betting Margins Explained
The ever-expanding world of online betting offers endless opportunity for bettors to handpick the best odds and bets from a wide array of offers.
Many bookmakers will claim to have the best-valued odds, but the burning question every tipster and punter is keeping their minds on is whether they will truly get the best deal for their money.
All of those who want to remain on top of things and always make sure they get the best odds possible need to make sure they understand how betting margins work.
What betting sites and bookies in general will do is adjusting the odds in order to attract bets from as many bettors as they can with a simple aim of securing a profit whatever the outcome may be.
The way they do this is by offering odds that often exceed the statistical probability of a chosen event, making sure they secure what is called a bookmaker’s margin. It is usually represented as the betting over-round or the market percentage with amounts over 100% and it is that difference between the actual value and the marketing value of a particular product – in this specific case a bet.
How do you calculate a betting margin?
If we are to bet on a match between Novak Djokovic and Andy Murray with Djokovic available at the betting odds of 1.65 and Murray standing at 2.35, the betting margin for this particular game will be:
(1/1)*100 + (1/2.35)*100 = 60.6 + 42.55 = 103.15%
This is close to 100%, so punters are getting a good deal, but the bookmaker has put in a 3.15% margin here, so if they have an even book, with the same amount of money placed on each player, their profit is 3.15% of the market.
Best 10 New Bookmakers
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£20 | SIGN UP HERE |
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18+. New players only. Deposit £20 and bet £20 in one transaction at odds of 2.00+ to receive a £20 free bet after settlement. Use within 7 days; stake not returned. Affordability checks apply. Terms apply. Gamble responsibly. GambleAware.org. |
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£20 | SIGN UP HERE |
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New verified customers only. Opt-in required. Deposit £20 and earn £1 of Free Bet value for every £1 staked on Bet Builders, with each qualifying stake counting towards a free bet builder reward, at combined odds of 2.0 (1/1) or greater. Min Reward: £1 Free Bet / Max Reward: £20 Free Bet. Cash in or claim within 48 hours of promo end. Free Bets expire 7 days after claim. 18+ GambleAware.org |
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£25 | SIGN UP HERE |
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New customers only. Bets placed on sports at odds of 2.50 or more to qualify. Bets must be placed 25 hours within registration. £25 free bets must be wagered on sports. Full terms below. Gambling can be addictive, play responsibly 18+ |
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£30 | SIGN UP HERE |
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18+ New customers only. Place a £10+ bet at min odds 1/1 (2.0) within 14 days of sign-up. Get £30 in Free Bets, valid for 7 days on selected bets only. Free stake not returned with winnings. T&Cs apply. BeGambleAware.org |
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£10 | SIGN UP HERE |
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Place qualifying bet within 7 days of reg (Min £10 at odds of EVS+). 2 x £5 free bets awarded once qualifying bet settles (18+). Full T&C’s Apply |
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£40 | SIGN UP HERE |
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Deposit £10+ and place a sports bet within 7 days from registration. Get 4 x £10 Free Bets - 2 x Football Accas (4+) & 2 x Sports Multiples (2+), valid 7 days. Min odds apply. Excludes virtual sports, esports and non-UK/IE horse racing. Opt-in required. 18+. T&Cs apply. |
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£10 | SIGN UP HERE |
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Welcome bonus for a new players only | Maximum bonus is 100% up to $/€/£ 123 | Min deposit is $/€/£ 10 | No max cash out | Wagering is 50x bonus | Maximum bet while playing with a bonus is $/€/£ 5 | |
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£10 | SIGN UP HERE |
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Place a minimum £10 single sports bet at odds of Evens (2.0) or greater. If your qualifying bet loses, you’ll receive a free bet within 24 hours. The free bet is valid for 24 hours and must be used on selections with minimum odds of 1/1 (2.0). Offer available to new customers only. Please gamble responsibly. |
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£10 | SIGN UP HERE |
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*#ad. 18+. Gamble Responsibly. Gambleaware.org. New customers only. £10 in real money. Bets placed on sports at odds of 2.00 ore more to qualify. Bets must be placed 24 hours within of registration. £10 free bets must be wagered on sports. Cashback is cash without restrictions. - Full Terms Apply |
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£30 | SIGN UP HERE |
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18+ New customers only. Opt in and bet up to £40 (min. £20) via mobile or app on any football (odds 1/1+) within 7 days of registration. Get up to £40 in free bets on selected markets, which expire in 7 days. T&Cs apply. GambleAware.org | Please gamble responsibly |
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