Reverse Line Movement: A trap for New Bettors

Maybe I’m grumpy fresh off a loss, but I’m convinced reverse line movement is a trap.

This will be a guide to reverse line movement, but I’m also going to cover why the common advice to follow and jump on reverse line movement is bad advice.

What is reverse line movement?

Reverse line movement is when the gambling line moves to make the more popular bet an even more attractive bet (higher payout in the case of moneyline or lower risk in terms of points spreads or over/under bets–see the types of sports bets if you aren’t sure what those mean). This is the opposite if what you’d expect the line to do. Normally when the sports books receive more bets on one team, they make betting on that team less desirable by subtracting odds from the moneyline or giving that team less points.

(if some of these betting terms like “giving less points” or “subtracting odds” are confusing, check out our guide on how to read sports betting odds)

Here’s an example taken from an email I received from PointsBet the day before writing this article:

They should that more than half of the total number of bets are on the Jaguars. Not only that, but well over half of the total money is on the Jaguars (the bigger money bets are also on the Jags). The Chiefs are favorites (it’s not clear from the picture but the Chiefs started -9). You’d expect with all the bets coming in on the Jaguars PointsBet would want to encourage people to bet on the Chief. To do this, they would give the Chiefs a more favorable line like -7. Instead, they did the opposite and made the line even more favorable for betting on the Jags. It ended -9.5 on the Chief (+9.5 on the Jaguars).

Why reverse line movement happens (and why people say you should follow reverse line movement)

Surprising fact: Sportsbooks like to avoid big losses.

They do this by creating the odds, so about half of people bet on each side. So when more than half of people are betting on one side, and the sports book moves the bet to make it more enticing to bet on that same bet, what are they doing?

There are 3 possibilities:

  • a sharp placed a bet on the other side
  • sportsbook models are relatively confident the majority of bets are on the wrong side
  • they expect more money to come in on the other side (maybe injury news, etc)

The most common reason is the first: a respected bettor put money on the opposite side of the popular line.

This is why so many people say you should follow reverse line movement and bet on the opposite side. It’s the sportsbook showing the sharp bettor’s hand, and saying hey the sharp’s are betting the opposite of everyone else.

And if you get a free betting tip from a sharp, why not take it?

The reason reverse line movement is a trap

So sounds like a gold mine, and bettors love this kind of thing.

But it’s often not. That’s why I wrote this article. The email example I used above? The Jaguars ended up losing by 7 points, so all those bets and money that came in on the Jaguars won (because they were either at +9 or +9.5 on the Jaguars). If you followed the reverse line and assumed the sharp bets were on the Chiefs, you would have lost.

This could be just chance – after all, no strategy is perfect.

But interestingly, while I was already writing this article, I received an email about reverse line movement in a today’s NFL game:

The Bills opened as 4 point favorites (-4 Bills). The majority of the bets and money went in on the underdog Bengals, but the sportsbooks weren’t phased by this action and actually incentivized more people to bet on the Bengals: they made the Bengals +6 and the Bills -6.

How’d the game end up? The Jaguars won the game. Reverse line movement strategy loses again.

Even though these are just two games, I’ve followed reverse line movement for a while, and it just doesn’t seem to work that often–at least more than any other random bet.

It’s a trap to blindly follow reverse line movement as a new bettor.

Reverse line movement is still worth considering

Okay, I just made the case on why you need to avoid reverse line movement.

It’s still valuable information. It still raises an eyebrow as to why Vegas is luring people into a bet that they’d lose a lot money of if it hit.

Most of the times Vegas probably has good reason to think the bet without much money on it is has the best odds. One important thing to remember if you’re going to use this information is small differences in spreads make a big difference.

So even if the sharps like the team you’re about to bet on, small point changes can make a big difference in their opinion.

For example, let’s use the bet above. The line starts at -4 for the Bills, and the Bengals get all the bets. The line moves to -6, which might be telling you a respected sharp put a big bet on the Bills at -4. So you decide to follow. Well, sad new is you’re not able to get the same bet as the sharp.

And armature bettors tend to think:

If the sharp wins his -4 bet, I’m likely to win my -6 bet. You’re right that you might win, but the problem is now you have to win two bets:

You have to win the same bet as the sharp AND you have to win the bet that if the sharp wins, your less favorable bet will also win.

Small differences = big money over time. It’s one of the “secrets” sharps know, but newer bettors really struggle to act on.

Check out my sports gambling guide for more actionable betting advice.