Common Mistakes Sports Bettors Should Avoid

Sports betting isn’t easy. If it was, sports bettors everywhere would quit their day jobs and live the sweet life betting on everything from the NBA and NFL to table tennis and cricket. If it was easy though, sportsbooks everywhere would go bankrupt, and the industry would eventually disappear.

While the average bettor typically loses more often than not, it is usually a matter of repetitions. Just like the sports and athletes that they bet on, most sports bettors just don’t have enough reps. They find it hard to maintain discipline and their bankrolls suffer.

If you are one of those bettors, don’t worry. You can build a solid bankroll over time. You just need to avoid these common sports betting mistakes. 

Not Sticking to Unit Size

We all love that huge bet at plus-money that pays out big time. The problem is that we often lose four to five, maybe even six bets in a row. We want so badly to make up for those losses, so we simply increase the size of our bet. That is a bad move.

Perhaps the most crucial discipline required to be a profitable sports bettor is bankroll management. Changing unit size according to performance is one of the worst things a bettor can do. Never double down and take more risk because you have the “sure thing” or because you’re on a hot streak. Likewise, never attempt to regain huge losses in one wager when you’re cold.

You should adopt a flat-betting strategy. Flat betting entails risking 1% to 5% of your bankroll per play and placing the same wager on each game. Three percent per play is a good medium. If your bankroll is $100, a $3 bet is smart. If your bankroll is $1,000, your 3 percent unit size would be $30. You get the idea.

When you encounter an unavoidably difficult period, a flat-betting strategy will prevent you from going bankrupt. But when it performs well, it will also give bettors a positive return on investment.

Recency Bias & Overreactions

Inexperienced bettors want to bet on a team just because they are hot or maybe they fade a team because they are playing poorly. Recently, the New York Yankees lost six straight games. That doesn’t mean that you automatically bet against them in their next game.

Oftentimes, teams are overvalued after a win. Sports bettors must be able to spot these instances. Take an NFL game, for example. The Kansas City Chiefs beat their last opponent by 21 points. They come into the next game, and they should be 7-point favorites. 

Sportsbooks know that the Chiefs are always a popular pick, so they will set the line at -7.5 or even -8 because they know that public bettors will bet on them regardless of the line or the price. As you become a more knowledgeable sports bettor, you will realize that 7.5 and 8 are usually bad (and expensive) numbers.

It’s the same on the other end. Teams can be undervalued, especially after bad losses. Good sports bettors learn how to spot these inconsistencies and take advantage of them.

Gambler’s Fallacy

We are only human, and our human brain can limit us as sports bettors. The gambler’s fallacy is this: something that has occurred more frequently than usual in a certain amount of time will occur less frequently in the future.

The Minnesota Twins won four games in a row. Since they’ve won four, they will probably lose their next game. However, the Twins went on to win 10 straight. They will surely lose the 11th, right? Not necessarily. The Twins did go on to win 13 straight before losing early in the 2025 MLB season.

Just because you may think something is “due” doesn’t mean it’s going to happen. It’s like watching the roulette wheel hit black eight times in a row. Your instinct would tell you to bet on red, but your reasoning is flawed.

Sporting events are independent of one another and should be wagered as such. Just because the Colorado Rockies have the worst record in baseball doesn’t mean that you automatically bet against them. Don’t fall into the gambler’s fallacy trap.

Too Many Bets

Many sports bettors love to bet and they want to bet on everything. That’s not a good idea. Never place a bet for the sake of having action on a game or games. Too many bets is too risky and you can destroy your entire bankroll with one bad night. 

Maintain self-control and stick to the bets in which you have the most confidence. Oftentimes, the best bet that you make on a given day is the one that you pass up. You can’t lose a bet that you never place.

Expectations

Do you really think you’re going to hit 70 percent of your bets? The professionals do it, don’t they? Well, no, they don’t. The best in this business come nowhere close to 70 percent. Keep in mind that you must win 52.38 percent of the time to break even on the standard-priced bet (-110). 

The best handicappers out there, guys (and girls) that do this for a living are extremely excited if their winning percentage is 55 percent. You should be excited too. If you can hit 55 to 60 percent of your bets over a given period of time, you are adding to your bankroll. 

Bet With Your Head, Never Above It

The betting public, which is everyone other than professional sports bettors, lose the majority of the time. If they didn’t, there would be a lot of sportsbooks out of business. Those public bettors are more interested in favorite teams and players. They typically like to see a lot of points scored. 

You can instantly think of teams and players the public favors. LeBron James, the Kansas City Chiefs, the Yankees, the Lakers, and so on. Public bettors like to choose favorites, and they love the Over when betting a game total.

The problem with always betting this way is that it is usually all based on emotion. You can’t bet on your favorite team simply because it’s your favorite team. Contrarian bettors, those that bet against the public, profit more often because of bias toward the public. 

Those contrarian bettors tend to position themselves with sharp bettors and sportsbooks. Remember, the house always wins. You can too if you bet with your head, not with your heart.

Shop for the Best Line

This is one of the easiest ways to make more money on your bets. Just like gas stations, there are numerous sportsbooks out there and they all have different pricing. Look at it this way. If you placed 400 moneyline bets at -110 and went 210-190, you would barely break even.

However, if you made the same 400 moneyline bets and had the same winning percentage, you would be up almost $1,000. That’s why you should look for the best line and best price on a game. 

If you can get an NFL favorite at -3.5, then why take them at -3 where the result could be a push? If that -3.5 favorite is priced at -115 at one book and -110 at the other, why would you not take it at -110? You’ll earn more on your payout.

Gaining those extra points or finding those better priced lines can add hundreds and even thousands of dollars to your bankroll over extended periods of time. With the number of sportsbooks available in the market, it pays to shop.