Coaches' adjustments can lead to different results in the second half. (Photo credit: Bridget Samuels / Foter / CC BY)
If you don’t do any halftime betting, you might want to start.
Halftime betting can be a valuable and profitable part of your portfolio for several reasons.
It allows you to make a bet after viewing half the game, it enables you to double up on your full-game bet if you like the way your team is playing, it gives you the chance to buy off a full-game bet if you don’t like the way your team is playing, and it provides an opportunity to middle your full-game bet as well. (Middling means having the opportunity to win both sides of a game without any risk of losing both bets.)
Totals
As a general rule, halftime totals are roughly half of the full game total. This makes sense, of course, since full game totals are based on more stats than just one half. But it also gives you a few opportunities to take advantage.
Over the years, there are a couple trends we’ve noticed with betting on football and basketball
In football, if the first half is much higher-scoring or lower-scoring than expected, the second half is often the opposite. Meanwhile, in basketball, if the first half is much higher-scoring or lower-scoring than expected, the second half is generally the same.
The football trend makes sense to us. Often when the first half is really high scoring or low scoring, a lot of things have gone right or wrong for the offences. Whether it’s a kickoff or punt return for a touchdown, fumbles in the red zone or interceptions deep in teams’ own territory, these things tend to balance out throughout the entire game.
Also, if a team gets lit up defensively or struggles offensively in the first half, guess where the coaches’ focal point will be at half time? Over a recent four-year span we tracked in the NFL, if a first half is a touchdown or more over or under the first half total, the second half went the opposite way about 55 per cent of the time – quite a healthy winning percentage.
The basketball trend is a little more puzzling to us. We always thought that if one team shoots the lights out in the first half (55 per cent or higher), they are likely to shoot a bit worse in the second half just because teams don’t generally shoot 55 per cent. Same with a team shooting 35 per cent in the first half – we would think the law of averages would mean the team would shoot much better in the second half.
But that hasn’t been the case, we’ve discovered by looking back over the last few years. When a first half is 10 points over or under the first half total, the second half goes the same way also about 55 per cent of the time.
Of course, shooting percentages are also related to the defence that is being played against the shooters. And scoring is also based on the pace of the game (how many shots are being attempted per minute) as well as how tightly the game is being called (plenty of free throws means plenty of points).
These things don’t usually change that much in the second half, which might explain why a low or high scoring first half often leads to a similar result in the second half.
Spreads
Unlike totals, spreads aren’t half the opening line. For example, just because the Packers are a 3 point favourite for the game doesn’t mean they will be a 1.5 point favourite in the second half. The second half spread is dependent on how the first half was played.
When heavy favourites are losing at the half, it’s usually a big surprise to the betting public. The Patriots might be down 10 points to the Lions, but there’s no way they’ll end up losing the whole game, right? Or maybe the Lakers are losing to the Clippers at halftime, a shocker considering the Lakers were 10-point favourites.
The oddsmakers know how the public is thinking. So halftime odds are very often shaded towards the favourite when the favourite is struggling.
That means the value bet is generally with the underdog. If the underdog’s been good enough that day to win the first half, why can’t they put up a similar fight in the second half? They might give up a good part of their lead in the second half, but you’ll still be catching a lot of points in a shorter time period than the full game if you take the underdog.
Line shopping is important
If you’re trying to make a profit at sports betting, the importance of line shopping shouldn’t be news to you. It’s always crucial to get the best possible line you can on each game, since so many games are decided by a point or half a point.
You could argue that line shopping matters even more when betting halftime lines, since a point in one half is worth twice as much as a point in a full game. Sportsbooks often have different numbers on halftime lines (both spreads and totals), so make sure you have accounts at multiple sportsbooks in order to get the best number.
Check out our recommended list of sportsbooks if you’re considering signing up at a few more books.