A steam move is a sudden, rapid line movement that occurs across multiple sportsbooks nearly simultaneously. It's caused by a coordinated group of sharp bettors — or a single large bettor with multiple accounts — betting the same side at different books before the market adjusts.
Identifying steam: - The line jumps 1-3 points within a short window (seconds to a few minutes) - The same direction of movement appears at multiple books nearly simultaneously - Movement is larger than typical injury news would cause - Timing doesn't align with obvious public news
Steam vs. drift: Not all line movement is steam. Gradual drift over hours or days often reflects slow public action. Steam is characterized by speed and synchronization across books.
Why it matters: Steam moves are the clearest signal of sharp money at work. If you can identify and bet the same side as a steam move, you're following the most informed bettors in the market. However, steam moves are often gone before most bettors can act.
Bet timing: Books respond to steam by moving the line immediately. Getting the number before the move or immediately after a steam move in the same direction can offer value. Chasing a number after it's already moved typically does not.