Definition
Steam chasing means trying to bet the old number after the market has already moved sharply. A steam move is a fast odds or spread change caused by heavy betting activity, often from respected accounts. Chasing it means the bettor reacts late and looks for a sportsbook that has not updated yet.
There is no special betting formula for steam chasing. The math is simple line value: compare the number you can still bet to the current market number. If Team A moved from -3 (-110) to -4.5 (-110), a bettor who finds -3 is getting 1.5 points better than the current market.
Worked Example
A college basketball favorite opens at -3 (-110). Within two minutes, most sportsbooks move to -4.5 (-110). One book still shows -3 (-110), so a bettor risks $110 to win $100 at the stale number.
If the game lands Team A by exactly 4, the -3 ticket wins while the current -4.5 ticket loses. That 1.5-point difference is the value being chased.
Why It Matters
Steam chasing helps when a bettor can capture a stale line before it updates. It fails when the move is already gone, limits are low, or the available number is no longer better than the market.