The easiest way to guarantee to make money betting on sports is arbitrage betting, also known as miracle bets or sure bets.  These cases occur when bookmakers have different opinions on a game and a bettor can make a profit regardless of the outcome.

Obviously the bookmakers do not love people who place arb bets.  You will easily be detected when placing large arbitrage bets and sometimes your bet will be cancelled and your account closed.

However, if you keep your bets small and make normal wagers as well you can use this trick to make a little extra money.  The key is to have accounts at several top sports books so you can shop around for opportunities.

You aren’t going to find many chances to place an arb bet on a major sport’s game line.  Each book monitors the NFL odds at several different locations, so they are going to make sure they fall in line and don’t leave themselves exposed to a large amount of money coming in on one side.

However, I’ve seen some nice opportunities on win totals, halftime bets, and futures odds.

The profit margins are going to be quite small.  You need a large bankroll so you can place some pretty large bets, but you’ll only get between a 1-3% return on your money wagered.  Say for instance you are able to find a 2% profit on an arbitrage and you are able to wager $3500, total action. Your return before the game even starts is only $70. Yes, you do have to put up $3500 to make that $70, but remember this is a risk free wager so normal money management principles don’t really apply.

The “risk-free” part isn’t entirely true because with the time it takes you to place a bet at one book, the other book you are using could have adjusted their lines, causing the middle opportunity to disappear.

Let’s use the Cincinnati Reds versus the Miami Marlins as a hypothetical game for an example. Assume the average line is Cincinnati –150 and Miami +140.

The first thing you do is shop for the best line on both sides of the game. After looking through your books, you find a possible arbitrage situation. You might see sportsbook #1 is offering Cincy –165 and Florida +155. After some more shopping, you come across another book that is offering different odds. Sportsbook #2 has Cincy –145 and Florida +135.

So what do you do? You are going to bet at sportsbook #1 on Florida +155 and at sportsbook #2 you bet Cincy –145. You now have bet on both sides on a single event. Sounds kind of crazy, but follow me here.

Let us assume you are going to bet $1000 on the “higher” dog. If you bet $1000 on Florida +155, how much do you want to wager on Cincy. If we do not do this correctly, we have a possibility to lose the arbitrage. I have a formula that will figure for you exactly how much money to wager on the –(favorite) per 1 dollar you bet on the +(underdog). So, If you bet $1000 on Florida at +155, the ideal number to bet on Cincy is 1.51 dollars for every dollar bet on Florida, or $1510 on the Marlins. Let’s break down the two possible outcomes.

If Florida wins, you “win” $1550 ($1000 at +155), while losing the $1,510 you bet on Cincinnati for a net gain of $40.

If Cincinnati wins, you “win” $1041.38, while losing the $1,000 wager on the Marlins for a total profit of $41.38.

As you can see, no matter who wins the game, you are coming out $40 ahead. Granted, you needed to wager a lot of money to do this, but you have totally negated any risk.

Sports Betting Arbitrage Formula

Remember that you must TAKE (T) the higher odds and LAY (L) the lower odds. The formula is based of off the odds you can get. In the above example the take (T) odds are 155, and the lay (L) odds are 145.

(T + 1) /( L + 1) x L = amount to lay per 1 dollar bet on the take odds.

So, in our example, our TAKE number is 1.55, and our LAY number is 1.45

e.g. (1.55 + 1) / (1.45 + 1) X 1.45 = 1.51

So, for every 1 Dollar bet at +155, we bet 1.51 at –145.

This next formula can be used to determine the percentage profit we are guaranteed.

(T – L) / L (T+2) + 1 = percentage won.

e.g. (1.55) / 1.45(1.55 + 2) + 1 = 1.6%

Arbitrage is a way to make money risk free with sports betting. If you see the chance to arbitrage a game, why not take it. It’s free money. You are using this formula to take a small advantage and make a little money from it.

The big question is, just how many chances are there for arbitrages per day/week/month? Therein lies the hard part. Chances like the one above are quite rare, but they are out there. What I suggest is that, now that you know what to look for, keep your eyes open for possibilities. If you happen to see a possible arbitrage situation, try to jump on it.

Instead of true arbitrage you can find yourself with plenty of middling opportunities.  While you don’t guarantee yourself a profit, you risk a small amount for a big payout.  These middle opportunities definitely arise more often.