Betting on football is unique when compared to the other major North American sports in a lot of ways. Perhaps the most significant is the amount of time that lines are available to be bet before the games are played. In baseball, basketball and hockey lines are typically available the night before the games are played – and sometimes not until the morning of the games. In the NFL the lines for most games on a Sunday afternoon are set the previous Sunday evening. That leaves much more time for the public and smart bettors to think about the lines and make their bets, and more time for the bookmakers to adjust the lines to balance their action. Because of that extra time it is more common in football than other sports to see lines that move significantly between when they are set and when the game is played. It’s not at all uncommon to see a line move by three points or more – a full field goal.

When lines move that much then the timing of your bet can make a big difference. If you are betting a favorite, for example, then you would much rather bet it at -4.5 than at -7.5 – in the former you can win by a touchdown and win your bet, while in the latter a touchdown margin of victory will lead to betting loss. The same in reverse is obviously true for underdogs as well – you would much rather bet an underdog at +7.5 than at +4.5. The challenge of timing your bets, though, is predicting when a line is going to move and in which direction it will move. If a spread is going to get bigger than the sooner you can bet on the favorite the better, while if you are betting on the underdog then waiting as long as you can before making your bet is likely the smartest move.

So, what causes football lines to move? As a basic rule, sports books like to have their action balanced – the same amount of money bet on both sides. When that happens then they are guaranteed to make a profit because the amount they have paid out to the winners is less than the amount they take in from the losers thanks to the juice. If the action gets unbalanced on one NFL team then the bookmaker will typically move the line to make the team that is drawing more of the bets less attractive. That can help to make the action more balanced, and will decrease the risk that the books are taking. By understanding where the greater percentage of the money is or is likely to be in a game, then, we can often predict how the line is going to move.

So, how can we guess where the money is likely to flow. There are two simple rules for NFL handicappers to keep in mind when getting started:

1. The public likes the favorite – All things being equal, the betting public prefers the favorite in most cases. The reason for this is simple – the public isn’t very sophisticated. That means that they don’t think about what team is likely to cover, but rather which team is likely to win. The favorite is obviously more likely to win in most cases, so they are more attractive for the betting public. Because the favorite is likely to be more attractive, the odds are likely to move to make the favorite less attractive and the underdog more attractive as the week progresses. As such, it is often a good idea to bet the favorite earlier in the week, and the underdog later in the week.

2. Public teams almost always draw the cash – There are some teams out there that the public absolutely loves, and will bet on in almost any situation regardless of who they are playing or what the spread is. Examples would include the Yankees, Lakers, Celtics, Red Wings, Patriots, and Colts. If teams like these are playing a struggling or poorly regarded team then the action is likely to be heavily tilted towards the public team, and the line is likely to make them less attractive as the week progresses. Jumping on these teams early in the week can be a good idea if you are sure you like them.

Those are both straight forward situations, but it’s not always as easy as that. There are several situations in which the line doesn’t move like we would expect it to. For example, sometimes a small number of professional bettors – the smart money – will bet significantly more money on an underdog than the larger number of public bettors will bet on the favorite. It easy easy to find out the percentage of bets that have been made on each side – several different websites publish that for free – but sportsbooks don’t generally release the amount of money that has been bet on either side. As a result we can’t always rely on the public betting tendencies. In cases like this – called reverse line moves – the favorite would actually get more attractive as the week went along despite the fact that the majority of bets form the public have been placed on them. Situations like that can’t always be easily predicted, so lines can easily move in exactly the opposite direction you would expect them to. The thing to keep in mind is that as a NFL handicapper you don’t have to bet on any particular game, so if you expect one kind of line movement and you don’t get it then you can just skip betting on that football game.