If you are gambling on a National Hockey League game and see -1.5 listed by a sportsbook, what you are looking at is what's known as the puck line. The typical betting options in most popular sports are the moneyline, the over/unders, and the spread. The puck line is hockey's version of the spread.
With a spread bet, or in this case a puck line wager, the vast majority of NHL games list a -1.5 for the team that is favored and a +1.5 for the team that is considered the underdog. The reason the number is so low is because NHL games are low-scoring compared to most other sports. As a result, the margin of victory also tends to be smaller compared to many sports.
With a plus or minus 1.5 betting line, the favorite must win by two goals for it to be a winning bet. On the flip side, the underdog can either win the game or lose by just one goal for you to collect on your bet. The reason a .5 is placed after the 1 is to make sure there is a winner and eliminate a tie, a.k.a. a push. In the event of a push, sportsbooks have to give the bettors their money back.
Puck lines are nearly almost always available in NHL games, although on occasion they are not. This is because the sportsbooks consider the teams evenly matched and aren't interested in making one of the favorites.
Smart bettors will consider a number of things when making a puck line bet and not just rely on a hunch. These include perusing various sportsbooks to look at their lines and see which would result in a better payout. You should also do your homework by studying the teams' statistics as well as how teams tend to play at home as opposed to away games.
Additional factors that can come into play are injuries, recent trades, time in between games, the travel time between games, and which team has the hottest goalie or scorer.
There's an additional reason many people prefer the puck line over the money line, which is simply picking which team you think will win. With the puck line, you increase your earnings on what you bet on the favorite because you are also beating the spread. Similarly, if you bet the underdog you can improve your chances of a winning bet because all it has to do is lose by less than two goals.
According to NHL statistics, games are decided by one goal between 33 to 50 percent of the time. This means you can often get a higher payoff by betting the underdog based on odds that are more in your favor. Studies have shown favorites have tended to do better in moneyline bets whereas underdogs have performed better on puck line bets.
Many NHL games go to overtime, so if you bet the underdog you will be rooting for the game to not be decided in regulation. This is because the first goal wins in overtime and an overtime game can only be decided by one goal.