What is a line move?
Line movement occurs when the odds or the point spread for a bet change leading up to the game. Line moves usually happen when more money is being bet on one side than the other.
A line might move because of an injury, change in coaches, the suspension of a key player, and other circumstances. But most often a movement happens because more money is wagered on one side of the bet.
In general, sportsbooks prefer to see total wagers distributed as closely as possible on each side of a bet. That way the sportsbook can make money no matter which team wins or loses. When more action lands on one side of a betting equation, the sportsbook risks losing money if that side ends up the winner.
The sportsbook can encourage more bets on the other side by changing the payout odds or shifting the point spread, or the over/under. More valuable odds, a reduction in the point spread, or a change in the sportsbook’s prediction of the final score are factors that can driver similar wager volumes to both sides of the bet by game time.
If the line moves after you have placed your bet, nothing changes for you. The odds or the line in place when you made your bet—printed on your ticket—won’t change for your bet, even if they do change on the odds board.