

| Regular Season | Playoffs | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Season | League | Team | GP | G | A | Pts | PIM | +/- | GP | G | A | Pts | PIM | +/- |
| 2012-13 | WHL | Tri-City Americans | -- | -- | -- | -- | -- | -- | 5 | 1 | 0 | 1 | 8 | 0 |
| 2013-14 | WHL | Tri-City Americans | 71 | 3 | 10 | 13 | 66 | -13 | 5 | 0 | 1 | 1 | 8 | -1 |
| 2014-15 | WHL | Tri-City Americans | 63 | 4 | 21 | 25 | 90 | -15 | 4 | 0 | 1 | 1 | 4 | -1 |
| 2015-16 | WHL | Tri-City Americans | 52 | 4 | 23 | 27 | 94 | 8 | -- | -- | -- | -- | -- | -- |
| 2015-16 | AHL | Providence Bruins | 7 | 0 | 1 | 1 | 0 | 3 | 1 | 0 | 0 | 0 | 0 | 0 |
| 2015-16 | WHL | Tri-City Americans | 52 | 5 | 22 | 27 | 94 | 8 | -- | -- | -- | -- | -- | -- |
| 2016-17 | NHL | Boston Bruins | 82 | 6 | 10 | 16 | 59 | 9 | -- | -- | -- | -- | -- | -- |
| 2017-18 | NHL | Boston Bruins | 76 | 0 | 6 | 6 | 45 | 10 | -- | -- | -- | -- | -- | -- |
| 2018-19 | NHL | Boston Bruins | 72 | 2 | 8 | 10 | 47 | 22 | 24 | 2 | 2 | 4 | 6 | 10 |
| 2019-20 | NHL | Boston Bruins | 67 | 4 | 15 | 19 | 33 | 16 | 13 | 0 | 1 | 1 | 8 | 0 |
| 2020-21 | NHL | Boston Bruins | 27 | 3 | 1 | 4 | 12 | 1 | 8 | 0 | 0 | 0 | 4 | 0 |
| 2021-22 | NHL | Boston Bruins | 79 | 6 | 9 | 15 | 31 | 2 | 7 | 0 | 1 | 1 | 6 | -5 |
| 2022-23 | NHL | Boston Bruins | 75 | 3 | 13 | 16 | 38 | 44 | 7 | 0 | 4 | 4 | 4 | 2 |
| 2023-24 | NHL | Boston Bruins | 76 | 4 | 10 | 14 | 42 | 23 | 13 | 3 | 1 | 4 | 6 | 4 |
| 2024-25 | NHL | Boston Bruins | 63 | 1 | 8 | 9 | 24 | 2 | -- | -- | -- | -- | -- | -- |
| 2024-25 | NHL | Toronto Maple Leafs | 20 | 0 | 3 | 3 | 13 | 4 | 13 | 0 | 0 | 0 | 8 | -4 |
| 2025-26 | NHL | Toronto Maple Leafs | 44 | 0 | 6 | 6 | 27 | 7 | -- | -- | -- | -- | -- | -- |
| NHL TOTALS | 681 | 29 | 89 | 118 | 371 | 140 | 85 | 5 | 9 | 14 | 42 | 7 | ||
| Year | Tournament | Team | GP | G | A | Pts | PIM | +/- |
|---|---|---|---|---|---|---|---|---|
| 2015 | World Junior U-20 Championships | Team USA | 5 | 0 | 1 | 1 | 0 | 1 |
| 2016 | World Junior U-20 Championships | Team USA | 7 | 2 | 2 | 4 | 4 | 9 |