Is T-Mobile Park a Hitters Park?
No. T-Mobile Park is a pitchers park. It scores 6% fewer runs than an average MLB park and allows 8% fewer home runs.
2026 park factors, three-year rolling averages. 100 = league average.
Why T-Mobile Park plays this way
Damp marine air and deep left-center — the most consistent pitchers park in the American League.
Home of the Seattle Mariners in Seattle, WA, opened in 1999.
What a park factor actually means
A park factor of 94 means runs are scored 6% less often here than at an average MLB park — comparing the same teams at home and on the road, so roster quality cancels out. The home run factor of 92 does the same thing for home runs only.
The two can disagree sharply, and that is the useful part. A park can suppress home runs while inflating runs, if the wall that stops fly balls also turns them into doubles. Read both numbers before deciding what a park does to a hitter.
Parks that play like this one
See it against the rest of the league
All 30 MLB ballparks ranked by park factor →
Park factors describe the stadium, not the player. To see what a hitter or pitcher actually produced, with the same formula applied everywhere, check the NUT leaderboard.