Point spread betting is the most popular way both American football and basketball are wagered online. It is also used as an alternative wagering option in other sports. To explain quickly: if the point spread lines in an NBA game are Lakers -3.5 / Celtics +3.5 here the minus sign (-) indicates the Lakers are a 3.5 point favorite. Those betting Lakers -3.5 would need them to win by 4 points or more, otherwise their wager is a loss. On the other side, the plus sign (+) indicates the Celtics are a 3.5 point underdog. Those betting the Celtics +3.5 win their bet if the Celtics win the game outright or lose by 3 points or less.
In this article I’ll discuss point spread betting in great depth including the ins and outs. I’ll also cover and link to intermediate betting strategy. First, if you’re already familiar with pointspreads, the following are my top 4 recommended online sportsbooks.
Because the point spread lines used often varies between online bookmakers it makes sense to shop the lines at all four bookmakers listed above. For example, if three sites have an NFL team -3, and you find another having -2.5 obviously you should make the bet at the site that is offering -2.5, so long as the odds are the same. There’s an old saying in sports betting “I know far more winning line shoppers than I do handicappers”.
Point Spread Betting Explained
Note: If you are experienced with sports betting you may wish to skim past or skip this section where I cover the very basics for the benefit of readers who are brand new.
The first thing to understand is point spread betting is only one of many ways to bet on a game from any sport. It is possible to bet just on which team will win with no point spread involved. To give an example let’s say in the NBA the Atlanta Hawks are one of the best teams and are playing at home against the Orlando Magic who are not a very good team and have injuries. The bookmaker might set odds on this game as Hawks -700 (risk $7 to win $1) / Magic +500 (risk $1 to win $5). This type of wagering is called moneyline betting. If you click that link you can learn more about betting on teams to win straight up.
The problem with moneyline betting is most gamblers prefer closer to an even money wagering proposition. With this in mind, for the same game the bookmakers will likely set the point spread odds as Atlanta Hawks -10.5 -110 / Orlando Magic +10.5 -110. The -110 is the price and means for every $1.10 you stake you’ll profit $1.00 if your bet wins. As you can see the odds are much closer to even, and I already explained how the point spreads work in the opening paragraph of this article.
Let me now explain some terminology and details you should be familiar with:
Betting Line – understand when someone asks “what is the line” they are referring to the point spread. In the used example the Atlanta Hawks have a line of -10.5 (spoken, “minus ten point five” or “minus ten and a half”) and the Orlando Magic have a line of +10.5 (spoken: “plus ten point five” or “plus ten and a half”). Another term sometimes used is: hook. What’s the line? “ten and a hook; Atlanta is the favorite”.
All Lines Have a Price – unless otherwise specified all point spread bets are -110 (risk $1.10 to win $1.00). In some cases the lines will be specified. You might see Hawks -10.5 -115 / Magic +10.5 -105. In this case the bookmaker feels the Hawks are slightly more likely to cover. The -115 means risk $1.15 to win $1 and the -105 means risk $1.05 to win $1.
Reduced Juice – popular US betting site www.5dimes.eu on game day offers point spread bets at -105 base. This does not always mean sides are -105, you might find Hawks -10.5 -104 / +10.5 Magic -106, or you might find -101 / -109, the point is that their reduced odds use a -105 base instead of a -110 base. You can find their reduced juice odds by looking under the column of the sport you’d like to wager and then clicking the box next to the word “reduced”.
Half-Points and Pushes – as already mentioned the half-point in a betting line is referred to as a hook. A line of -10.5 has a hook where a line of -10 does not. With -10.5 it is not possible to tie. With -10 it is possible to tie. In the event you do tie, for example betting -10 and having your team win by exactly 10, this is called a push. In this case your stake is returned and the outcome is as if you never placed the bet.
Line Shopping is Key
The importance of line shopping cannot possibly be understated. If for NBA basketball you were to beat the consensus point spread by an average 1-point (for example: bet +7 when most sites have +6), as long as you managed your bankroll well, it would be near impossible to lose over the long-haul. Also the difference between betting -3 -105 and -3 -110 is massive. At -105 you only need to win 51.22% of your wagers to break even. At -110 you need to win 52.38%. Understand line shopping is not always easy.
An example where a decision comes into play: let’s say for an NFL football game the New York Jets are +6.5 -110 at all websites but Bovada has +7.0 -120. This is a difference of risk $1.10 for each $1.00 you want to win or risk $1.20 for each dollar you want to win. Is the extra half-point worth it? How do we decide? This is where this article gets slightly more advanced than the basics.
In order to decide if +6.5 -110 or +7 -120 is a better bet we need some sort of a base to work with. If you’re a handicapper you can probably handicap the probability that a +6.5 wager wins. Considering you’re reading this article you’re likely not a handicapper. My advice is to gain this base by calculating the no-vig market price using odds from www.pinnaclesports.com. They don’t accept US players but that’s okay, we’re not betting here – we’re simply using them to gain information. For the reason on why to use Pinnacle refer to my article: the evolution of the betting market.
How to Calculate No-Vig Probability
Let’s say the odds at Pinnacle are Patriots -6.5 -105 / Jets +6.5 -103. The first thing we need to do is convert -103 and -105 to required break even percentage (also referred to as implied probability). We can do this using our odds converter. Enter -105 under American odds and see this is 51.22% and enter -103 and see this is 50.74%. Notice if we add these two probabilities together 51.22%+50.74% is 101.96%. The reason the probabilities are higher than 100% is due to the vig (also known as juice or markup) which is how the bookmakers earn profit.
To remove vig from the probabilities divide each by the total probability. In this case the math is 51.22%/101.96%=50.24% and 50.74%/101.96%=49.76%. Notice 50.24%+49.76%=100%. We’ve now calculated the no-vig probabilities. This is telling us the market no-vig probability for Jets +6.5 is 49.76%. We now have a point spread probability needed to evaluate whether +6.5 -110 or +7 -120 is a better bet.
Calculating Bet Value with Different Half Points
We now know +6.5 is expected to cover 49.76% of the time. To calculate the fair percentage for +7 we need to figure exactly how often underdogs will lose by exactly 7 points. For this I’ll use the -4 to -9 column of the NFL push chart mikevegas posted on Roughing the Punter. Here I see +7 exact is expected 6.0% of the time. Understand when moving from +6.5 to +7 we are only picking up half of that 6%. The other half is in our opponents -7 line, while half is in our +7 line. So expected cover/push rate of +7 is the 49.76% for 6.5 plus half of the 6%. This is 49.76%+(6%/2)=52.76%.
So what we now know is we expect +6.5 covers 49.76% of the time and +7 covers 52.76% of the time. So which is the better bet +6.5 -110 or +7 -120? For this we use the EV equation: (win probability * what you’ll be paid if you win) – (loss probability * amount staked)=EV.
First we need to use the same stake for them both, so we’ll say $100. At -110 a $100 bet pays $100/1.1=$90.909 and at -$120 a $100 bet pays $100/1.2=$83.333. We now have all the data we need to use that equation.
- +6.5 -110 solves as (0.4976*$90.909)-(0.5024*100)=Negative (-)$5.00
- +7 -120 solves as (0.5276*$83.333)-(0.4724*$100)= Negative (-)$3.27
Here we’ll note both lines are –EV, however staking $100 on +7 -120 will average less of a loss than staking $100 on +6.5 -110. So if we must bet here we’ll go with the +7 -120 option.
Not All Point Spreads are Equal
It is important to understand that not all point spreads are equal. Take baseball, according to the book Betting Baseball by Michael Murray, when home teams win it is by exactly 1 run 31.7% of the time. When the road teams win it is by 1 run 23.6% of the time. The reason why should be obvious. When the home team takes the lead in the bottom of the final inning, they only go up by 1 run, unless the game ends in a walk-off home run. The actual probability depends on the moneyline and game total. Just when two teams are evenly matched understand +1.5 for the road team is much greater value than 1.5 for the home team.
In American football there is a huge disparity between the values of specific point spreads. For example in NFL football -5.5 -110 and -5 -114 have about the same difference in value as -3 -110 and -2.5 -135. That’s a 4 cent and a 25 cent change when moving a half point on each. This could actually be better stated that when dealing with market prices -5.5 -110, -5 -114, -3 -110 and -2.5 -135 all have the same expected value. The reason for the difference is 3 is the most common margin of victory in football, where games are decided by 5 points only on rare occasions.
The same is also true in basketball but only to an extent. For large point spreads say over 10.5 the distribution is far more random. However, as explained in my article buying-half points in basketball end game strategy in close games makes certain small point spreads more likely to occur.
In other games like soccer, ice hockey and field hockey where goals are scored one at a time with a low frequency per match, half points are worth a ton.
In order to analyze all this you’ll need to develop push charts. How is covered in my detailed article on football teaser betting. For more on the topic of point spread betting you may wish to read the articles I already linked to here, as well as buying half points in football and basketball teasers. You can also follow additional links from inside those articles to gain a much better understanding of how to bet sports with an advantage. This article here has provided you a decent overview. We encourage you to read further and wish you the best of luck.