There are different names for sports arbitrage opportunities; all of which refer to the same style of betting. The most popular is 'arbs', while other names are overbrokes, surebets, underrounds, all carrying exactly the same meaning. Arbitrage sports bettors are able to get near guaranteed profits by locating the highest odds on each participant and placing their bets with different bookmakers accordingly.

"Arbitrage sports betting" is a system of betting on the outcome of events to net a profit regardless of the results. It involves exploiting the differences in the odds that bookmakers offer on different participants. Arbitrage bettors, sometimes known as 'arbitageurs', place their bets on every selection of a sporting event in a manner that ensures them a profit no matter who the winner is. It is a way of gambling for assured returns and is termed as no risk gambling.

The toughest part is finding at least two different bookies whose prices differ, and the difference is high enough to create an arbitrage opportunity that can provide a profit. To state it simply, you bet on one participant with one bookie and bet on the other with another bookie. The odds offered by each of the bookies should be substantially different and will be the basis to determine the amounts that need to be wagered on each participant to create a money-making arbitrage bet.

For example, in tennis, let's suppose Andre Agassi is playing against Patrick Rafter. Bookmaker A offers 1.91 for Agassi and 2.39 for Rafter. Bookmaker B offers odds 2.2 for Agassi and 1.72 for Rafter. This presents an opportunity to use an arbitrage bet to provide guaranteed profits no matter who wins. Suppose you are prepared to invest $500, what can be a good system? Let's create a theoretical bet:

On Agassi - $267.64 with bookie A

On Rafter - $232.36 with bookie B

Total Investment is $500

Let's suppose now Agassi wins. You bet on $267.64 on Agassi with bookie A

Agassi with odds of 1.91 with bookie A works out as 267.64 x 1.91= 511.19

Remember that your total investment between both bets was $500. Take that away and your net profit works out to be $11.19.

Now let's suppose Rafter wins. You bet $232.36 on Rafter with bookie B.

Rafter with odds of 2.20 with bookie B works out as 232.36 x 2.20= 511.19

Once again, your total investment between both bets was $500. Take that away and your net profit works out to be $11.19 once again. You can't lose! The profit is assured.

Arbitrage sports betting is often portrayed as risk free, however, it is not entirely free of risks. For one, the bookmakers have their odds balanced and if you back both sides with the same bookmaker you are sure to lose. Arbitrage will only work when you place your bets with two different bookmakers who, for their own reasons, offer different odds for the same event. They may also shorten their odds after a certain amount has been received against the bets and this will kill your chance of making a profit. Bookmakers also restrict the amount they accept from one person against a selection and even if you would like to put in a bigger amount against your bet, you may not be able to do so.