Sports Betting Lessons: Arbitrage Betting

Sports Betting Lessons

By Professor MJ

Arbitrage Betting


This is a topic I know all too well since my whole life was heavily oriented towards this form of gambling for several years: arbitrage betting.

Some of you may already have a good idea of what it is and may be looking for tips on how to be more effective.

For others, it will be a real eye opener and will blow you away. I know I got super excited the first time I heard about arbitrage betting, and back then I did not know it would have such a huge impact on my life.

1. Introduction

Most people believe risk-free sports betting is impossible to achieve. Yet, I am about to show you how it can be done. I am not talking about having a 99% chance of winning your bets: I’m claiming it can be 100%.

I hate it when sports handicappers advertise some picks as being “the lock of the century” or “100% guaranteed” or that you should bet your house/wife/kids on a certain team. So how can I be having a similar speech?

Because there is a different twist to it. We are not going to bet on one of the two teams playing head-to-head; we are going to bet both teams with a guaranteed profit on the horizon.

Each casino has its own set of odds on every game. When odds on a specific game differ significantly enough between two bookies, you will have the opportunity to bet both teams while guaranteeing yourself a net profit. This is what’s called an “arbitrage opportunity”.

2. Example

Let’s see how it works with a fictitious example.

It is vital that you are comfortable dealing with odds in American format in order to understand the following. If you are not there yet, don't panic! I wrote an article dealing specifically with this topic; read it here. If you don't understand American odds, you will quickly feel lost.

Fictitious example - arbitrage opportunity (sports betting)

Suppose you place a $1000 bet on Team A with the first bookie. Your potential return is $1000 * 1.714 = $1714 (a $714 profit).

Now, assume you also wager $700 on Team B with the second bookie. The potential return for that bet turns out to be $700 * 2.45 = $1715 (a $1015 profit).

Overall, you’ve made the following two bets:

  • Team A: risking $1000 to win $714
  • Team B: risking $700 to win $1015

Assuming no ties are possible, there are two possible outcomes:

Two potential outcomes from an arbitrage opportunity (risk-free sports betting strategy)

As you can see from the table above, you are netting a $14 profit in the eventuality of Team A winning the game, while earning a $15 profit if Team B gets the victory.

Unlike standard betting where you are backing a single team and worrying about them succeeding, you can sit back and relax knowing you will be richer at the end of the day.

Your first reaction might be as follows: “I need to bet $1000 on one side and $714 on the other side, only to end up $14-$15 richer? Geez, is it really worth it?”

I’m going to address this question in a short while; first, let me discuss the important issue of how to quickly detect such guaranteed profit opportunities.

3. How to Quickly Detect Arbitrage Opportunities

If you want to be serious about arbitrage betting, you need to be proficient and comfortable with American odds. You will save precious time by looking at odds in American format (as opposed to decimal format), which can be the difference between a missed opportunity and a profitable one.

Let’s go back to the example above, but this time focusing solely on American odds:

Arbitrage opportunity presented with American odds

How can you tell in the blink of an eye whether you have an arbitrage opportunity or not? Here is the crucial rule:

The number next to the “plus” sign, associated with the underdog’s odds, must be GREATER than the number next to the “minus” sign, corresponding to the favorite’s odds.

You might want to reread the sentence a couple of times before it sinks in.

Basically, you start by looking for the best possible odds on the underdog. In this case, it can be found with Bookie #2 at +145.

Now, what are the best odds on the favorite? You’re right, they are -140 with Bookie #1.

You are then hoping that the number associated with the underdog, 145, is greater than the number connected to the favorite, 140. Since 145 is indeed a higher number than 140, you should hurry up and take advantage of this favorable situation.

Just to make sure things are crystal clear, let’s consider another example where this time we are looking at odds from five different casinos:

Is there an arbitrage opportunity with these five sportsbooks? No!

The team established as the underdog is A since the “plus” signs are associated with them. What are the highest odds on Team A? They can be found with Bookie #4 at +187.

What about Team B? If you wanted to bet them, the smartest decision would be to bet with Bookie #3 at -190.

Since the number associated with the underdog, 187, is NOT greater than the figure related to the favorite, 190, you cannot guarantee yourself a profit by betting this match. Just move on to the next game.

4. Tips to Increase Your Winnings

Let me go back to the question I raised earlier: is it all worth it (betting a total of $1714 to earn a guaranteed $14-$15 profit)?

First of all, some arbitrage opportunities will be more rewarding than others: it depends on how much the odds differ from one sportsbook to the other.

That being said, let me give you some advice to maximize your sports investment money.

Tip #1: Opening an account with non-sharp sportsbooks

The amount you can earn on a daily basis depends on how many opportunities you can find.

In this regard, it is fundamental that you find bookies that are not “sharp”, which means they are slow to move their lines, or they tend to favor some teams too much.

In other words, you need to find sportsbooks whose lines differ from the general consensus.

Tip #2: Focus on Less Popular Leagues/Sports

I started getting involved in the sports gambling world back in 1999-2000, specifically with the intention of doing arbitrage betting.

Back then, the opportunities were plentiful. I spent lots of days and evenings tracking lines on all sports and leagues, including some I absolutely knew nothing about, which wasn’t important for my purpose.

As years went on, it became more and more difficult to find good opportunities because bookmakers made the appropriate adjustments. Nowadays, the lines are more similar from one bookie to the other.

Unlike the early 2000s, online gambling is now very popular. With so many bettors around the world, whenever a bookmaker has odds that are dissimilar to others it will almost immediately receive heavy action, especially on major sporting events where arbitrage occasions are seldom seen.

That’s why I will provide the following recommendation if you have the intention of getting into arbitrage betting: don’t waste your time tracking money lines, spreads or totals on major sports like the NFL, the NBA, the NHL, MLB or the most important soccer leagues. You can expect to earn less money doing this than if you get a job at McDonald’s.

You will need to get off the beaten paths and investigate more obscure sports/leagues.

Tip #3: Looking at "Proposition" Bets

That is actually a great source of arbitrage opportunities. In case you do not know what “prop” bets are, here is Wikipedia’s definition: “Proposition bets in sports are differentiated from the general bets for or against a particular team or regarding the total number of points scored.”

Here are a few examples: which team is going to score first, will there be a run scored in the first inning of a baseball game, how many sacks will be recorded by both teams during a football game, will the largest lead of the game be over/under 15.5 points, etc.

Many people also enjoy betting “player props”, which are bets regarding the performance of a specific player.

A few quick examples: will player X score at least a goal, will player X score over/under 26.5 points, will quarterback X throw at least one interception (American football), will player X make or miss his first 3-point attempt (basketball), etc.

The number of possible proposition bets is only limited by the oddsmakers’ imagination. A very large number of prop bets are offered on the Super Bowl which, by the way, is by far the best money-making event when it comes down to arbitrage. Historically there have been several weird bets on that game:

  • What color Gatorade will the winning coach get doused with?
  • How long will the national anthem singing last (over/under 2 minutes, for instance)?
  • Will the power go out during the game?

Tip #4: Having Multiple Sportsbook Accounts

One more tip related to successful arbitrage betting: the more accounts you have, the more opportunities you will find.

I personally started off by having an account with 2-3 sportsbooks. At the peak of my arbitrage career, I had 10. Obviously, you have a better chance of finding profitable situations when comparing odds from 10 different bookies. However, you need more capital.

An interesting side effect of doing arbitrage is receiving bonuses from casinos. Almost all of them offer signup and reload bonuses. So not only are you betting risk-free, but you are also receiving an additional benefit.

5. Pitfalls

It wouldn’t be fair to end this article without mentioning the drawbacks from this form of gambling (if we can call it gambling!):

Pitfall #1: Line Moves

Once you have identified an arbitrage opportunity, the process is not totally risk-free. The most common source of losses comes from line moves.

Suppose you are about to bet Team A at -140 odds and Team B at +145.

You make some quick calculations to determine the amount you are going to bet on each side, you place your bet on Team A, and as you are preparing yourself to bet Team B you realize the line has moved to +135. Unless another bookie has a line of at least +140, you are doomed to lose some money in the process.

Here is a tip: place your first of two bets on the line that seems the most out of whack.

Imagine you have five accounts and the line is set at -140 on Team A with all bookies, except one that has Team A at -153 and Team B at +143.

You absolutely need to rush and first bet on Team B at +143 odds. Once that is done, even though you try betting Team A at -140 with a certain bookie and the line changes, you still have three more bookies with the -140 line. It’s pretty unlikely that their lines will all change.

Pitfall #2: Betting the Same Team Twice (that's embarrassing!)

This may sound ridiculous, but trust me it is likely to happen to you if you pursue a long arbitrage career: betting the same team twice.

I'm ashamed to admit it, but I’ve made this dumb mistake before. And I know several people who have also done it. Once you have found a good occasion, the adrenaline rush kicks in and since you are aware of the potential line moves you try to act as fast as possible.

What generally happens when we try to do things too quickly? That’s right, we make mistakes.

Instead of placing one bet on Team A and one bet on Team B, you end up wagering on Team A twice.

You might realize right away that you committed a big mistake, in which case you will have two options: hedging or taking a gamble.

By hedging, I mean betting a sufficient amount on Team B to prevent huge losses if Team A loses the game. If you go the hedging route, you will likely have guaranteed losses, but it won’t be a devastating blow to your bankroll.

The second option, taking a gamble, is simple: you cross your fingers, hoping Team A wins the match. It’s up to you. 

It is also possible that you bet the same team twice but don’t realize it until you check your account balances the next day. It could be a thrilling experience or a crushing one, depending on the outcome. Trust me; it really hurts when you realize you have just lost your entire winnings from the past 2-3 months of hard work.

The best way to avoid such huge losses is to log your bets in an Excel file after you are done placing them. When you check your betting history in your bookie’s accounts, you will notice the error if there is one.

Pitfall #3: Too Late! The Game has Started!

There are more line moves close to game time. The public is excited about the game which is set to begin and more betting action occurs.

That creates more line movements, and therefore more chances of finding arbitrage opportunities.

The big danger here is to bet Team A, only to realize it’s too late to bet Team B because the line is now off the board. Be aware of this risk; you could elect to bet smaller amounts under such circumstances.

Pitfall #4: Not Being Able to Bet the Desired Amount

Always be aware of each casino’s betting limits.

Assume you were planning to bet $500 on Team A and $800 on Team B. You start by wagering on Team A, but as you execute the bet on Team B you realize you are not allowed to bet more than $300.

If you are lucky enough, you might find another bookie that offers similar odds, otherwise you might have to bet on weak odds while guaranteeing yourself a loss instead of a gain.

Pitfall #5: Getting Limited or Banned by the Sportsbook

Some bookmakers don’t mind dealing with “sharps”, but others hate it. Once they realize you only make smart bets, they might react by lowering significantly your betting limits.

This phenomenon is most common when you only focus on proposition bets, which is something they don’t like to see.

Alternatively, they could politely ask you to cash out and leave. If you are playing with reputable casinos, they are pretty unlikely to steal your money. 

All of the above warnings may sound like there are a lot of pitfalls. As you gain more experience, you will get better at avoiding them. I just wished someone had told me about them before I got started: you are getting a head start by being forewarned!

6. Current Status and Future of Arbitrage

I mentioned earlier that arbitrage opportunities were in abundance in the early 2000s, but were now more difficult to find these days because more and more bookmakers copy each other’s odds. It may sound like arbitrage is slowly dying.

However, it has regained some momentum, thanks to the skyrocketing popularity of “live betting” (also called "in-play wagering").

In the early days of online gambling, you could only bet a game before it actually began and perhaps at the halftime break (betting the outcome of the second half).

Nowadays, almost all bookies offer “live betting”, where you can place wagers throughout the match as casinos update their odds based on how the game plays out.

That has opened up a whole new world of arbitrage opportunities. Things are happening very quickly and casinos don’t have time to verify whether their odds are in line with others.

In other words, live betting is another area where I strongly recommend tracking lines because you will find profitable situations if you are patient enough. Keep in mind, though, that pitfalls described above are more present than ever with this type of gambling due to its fast-paced nature; as a matter of fact, lines are moving very frequently.

7. Don't Miss Out!

I have written other articles teaching sports betting lessons which should be useful to you. For example, I've covered the form of gambling I’m personally using the most these days: value betting. Be aware that you’ll need your mind to be extremely sharp because there will be even more mathematics and calculations involved. But trust me, it is really worth it!

If you like the work I’m putting up for free and want to be updated on what I have been up to, you could either subscribe to my mailing list, which can be done from the homepage of (at the very bottom), or better yet, join my friendly Facebook group where I occasionally run some free prediction contests where you can win cash or prizes! You will also gain exclusive access to my NFL picks and specific winning strategies in the NFL, NHL, NBA and MLB!

Thank you very much for reading this article. Keep educating yourself about sports betting as this is a wise investment of your time, and I hope this website can contribute towards that goal. This is Professor MJ, it was great talking to you, and I hope to talk to you again soon!

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