Although there’s no sure bet in the world of gambling, arbitrage betting is about as close as you can get. Basically, arbitrage betting or arbing, as it’s commonly known, is a way of exploiting bookmakers’ differing odds in order to make a profit on sports betting.

Arbitrage betting usually works best in more obscure markets, because this is where bookmakers more often have differing opinions on a game’s outcome. Arbers must work fast to identify the opportunity and place the bets before the odds are adjusted as bookmakers employ advanced software to make sure such difference in odds doesn't exist for long.

In a working example, you’re looking to place a bet on a tennis match with Roger Federer (Player 1) and Stan Wawrinka (Player 2). One bookmaker has odds of 1.3 on Federer winning and 3.93 on Wawrinka, while the second has 1.42 placed on Federer and 2.9 on Wawrinka.

If you put €734.1 at 1.42 on Federer with the second bookie and  €265.9 at 3.93 on Wawrinka at the first bookie, regardless of which Player wins, you will pocket €1043 out of €1000 initial investment, thus making a SURE PROFIT of €43. So either way, you win.

The exact mathematical formula to calculate the needed stakes is as follows:

Sum of Implied Probabilities = ((1 / decimal odds for Player 1 to win) x 100) + ((1 / decimal odds for Player 2 to win) x 100)

((1 / 3.93) x 100) + ((1 / 1.42) x 100)) = 25.5% + 70.4% = 95.9%

Every time the sum of implied probabilities is lower than 100%, an arbitrage opportunity has presented itself.

Individual bets = (Investment x Individual Implied Probability %) / Sum of Implied Probabilities %

Individual Bet on Player 1 at 1.42 = (1000 x 70.4%) / 95.9% = €734.1

Individual Bet on Player 2  at 3.93 = (1000 x 25.5%) / 95.9% = €265.9

Source: Pinnacle

Some sites state that arbing is a surefire way to make a profit, but it’s not without its pitfalls.

After all, it’s called “gambling” for a reason. There is always some risk involved, even if it’s minimal.

Though it can lead to big wins for arbers, this form of betting is not liked by bookmakers and when detected, your accounts may be limited to small stakes only or even completely closed. Only a few bookmakers are arbitrage friendly. One of them is Pinnacle, you will never get your account limited there, but of course they manage their odds carefully and you will rarely find arbing options with them. Another must have for arbers is Betfair, but in their exchange, you have commission and should have in mind that the real odds are lower than the displayed.

Another serious danger is that one of the odds may become unavailable or decreased while you are betting the other one. For example, while you are placing your bet on Player 1 at 1.42 in Bookmaker B,  Bookmaker A might adjust the odd for Player 2 down to 3.40 and you end up with an open position on Player 1 and no chance to make arbitrage anymore.

Other problem could arise from different rules of bookmakers. In the above example, if Wawrinka retires during the 1st set it is possible that some bookmakers void the bet on Federer to win, while in other bookmakers your bet on Wawrinka will be lost. That is why especially for tennis is very important to know the exact retirement rules of each bookmaker you use.

In addition to the drawbacks listed above, bettors who use this system will need to have multiple accounts, and not all of those accounts will have sufficient funds at all times. One account may be plentiful, while another may be close to being overdrawn. Keeping all of your money in one account makes it easier for bookmakers to catch on that you are engaging in arbitrage betting.

In order to succeed at this type of sports gambling, the bettor really has to know what they are doing, and know how to act quickly and knowledgeably. It’s also a good idea not to make huge bets but to bet small stakes at a time until you can figure out the proper way to succeed. Once you’ve got it down, you can really begin making some nice profits.

There are also a number of sites that can help with signals for arbing opportunities, but again, you must do your research to ensure that they are a reputable business. Our partner RebelBetting has a great software for finding and placing surebets, so if you're looking into arbing, make sure you read the review of RebelBetting or give it a try.