
| Player | Date | P | Comment |
|---|---|---|---|
| 10/18/2026 | SG | Waived (The Boston Celtics waived (G) Hayden Gray.) | |
| 10/18/2026 | F | Waived (The Boston Celtics waived (F) Tucker DeVries.) | |
| 10/18/2026 | PG | Signed/Offer Sheet (The Boston Celtics converted the contract of (G) Devin Carter to a two-way contract.) | |
| 10/18/2026 | G | Waived (The Boston Celtics waived (G) Milos Uzan.) | |
| 10/18/2026 | PF | Waived (The Boston Celtics waived (F) Gabe McGlothan.) | |
| 10/1/2026 | F | Signed/Offer Sheet (The Boston Celtics signed (F) Tucker DeVries.) | |
| 9/23/2026 | PF | Signed/Offer Sheet (The Boston Celtics signed (F) Gabe McGlothan.) | |
| 9/23/2026 | SG | Signed/Offer Sheet (The Boston Celtics signed (G) Hayden Gray.) From Utah | |
| 9/17/2026 | G | Waived (The Boston Celtics waived (G) Caleb Grill.) | |
| 9/15/2026 | G | Signed/Offer Sheet (The Boston Celtics signed (G) Caleb Grill.) | |
| 9/14/2026 | PG | Signed/Offer Sheet (The Boston Celtics signed (G) Devin Carter.) | |
| 8/5/2026 | SF | Signed/Offer Sheet (The Boston Celtics signed F Dillon Mitchell to a two way contract.) | |
| 7/9/2026 | PG | Waived (The Boston Celtics waived F Dalano Banton.) | |
| 7/1/2026 | PF | Traded (The Philadelphia 76ers traded F Paul George to the Boston Celtcs.) From Philadelphia | |
| 7/1/2026 | SF | Traded (The Boston Celtics traded G-F Jaylen Brown to the Philadelphia 76ers.) To Philadelphia | |
| 7/1/2026 | C | Signed/Offer Sheet (The Boston Celtics signed C-F Mitchell Robinson.) | |
| 7/1/2026 | PG | Signed/Offer Sheet (The Boston Celtics signed G Mike Conley.) | |
| 6/30/2026 | PF | Signed/Offer Sheet (The Boston Celtics signed F-C Amari Williams to a two-way contract.) | |
| 6/30/2026 | SG | Declared Free Agency (G John Tonje elected free agency.) | |
| 6/30/2026 | SG | Declared Free Agency (G Max Shulga elected free agency.) | |
| 6/29/2026 | PF | Declared Free Agency (F-C Amari Williams elected free agency.) | |
| 6/29/2026 | C | Declared Free Agency (C Nikola Vucevic elected free agency.) | |
| 6/26/2026 | G | Signed/Offer Sheet (The Boston Celtics signed (G) Milos Uzan.) |