| | LW | Sent to minors (The Boston Bruins sent F Jeffrey Viel to the minors.) |
| | LW | Called up from minors (The Boston Bruins recalled F Jeffrey Viel from the minors.) |
| | LW | Sent to minors (The Boston Bruins sent F Riley Tufte to the minors.) |
| | C | Sent to minors (The Boston Bruins sent F Patrick Brown to the minors.) |
| | D | Placed on Injured Reserve (The Boston Bruins placed D Hampus Lindholm on injured reserve.) |
| | LW | Called up from minors (The Boston Bruins recalled F Riley Tufte from the minors.) |
| | C | Called up from minors (The Boston Bruins recalled F Georgii Merkulov from the minors.) |
| | C | Called up from minors (The Boston Bruins recalled F Patrick Brown from the minors.) |
| | D | Called up from minors (The Boston Bruins recalled D Jordan Oesterle from the minors.) |
| | C | Sent to minors (The Boston Bruins sent F Matthew Poitras to the minors.) |
| | D | Signed (The Boston Bruins signed D Loke Johansson to an entry-level contract.) |
| | LW | Sent to minors (The Boston Bruins sent F Max Jones to the minors.) |
| | C | Signed (The Boston Bruins signed F Tyler Johnson.) |
| | LW | Called up from minors (The Boston Bruins recalled F Riley Tufte from the minors.) |
| | LW | Waived (The Boston Bruins waived F Riley Tufte.) |
| | C | Activated (The Boston Bruins activated F Matthew Poitras from injured reserve.) |
| | D | Waived (The Boston Bruins waived D Ian Mitchell.) |
| | D | Placed on Injured Reserve (The Boston Bruins placed D Ian Mitchell on the Injured Reserve.) |
| | D | Placed on Injured Reserve (The Boston Bruins placed D Alec Regula on the Injured Reserve.) |
| | C | Released (The Boston Bruins released F Tyler Johnson.) |
| | C | Placed on Injured Reserve (The Boston Bruins placed F Matthew Poitras on injured reserve.) |
| | G | Sent to minors (The Boston Bruins sent G Kasimir Kaskisuo to the minors.) |
| | G | Sent to minors (The Boston Bruins sent G Ryan Bischel to the minors.) |
| | C | Waived (The Boston Bruins waived F Patrick Brown.) |
| | RW | Sent to minors (The Boston Bruins sent F Fabian Lysell to the minors.) |
| | D | Sent to minors (The Boston Bruins sent D Jackson Edward to the minors.) |
| | C | Sent to minors (The Boston Bruins sent F Brett Harrison to the minors.) |
| | D | Sent to minors (The Boston Bruins sent D Michael Callahan to the minors.) |
| | C | Sent to minors (The Boston bruins sent F Riley Duran to the minors.) |
| | C | Sent to minors (The Boston Bruins sent F Jaxon Nelson to the minors.) |
| | C | Sent to minors (The Boston Bruins sent F Georgii Merkulov to the minors.) |
| | D | Waived (The Boston bruins waived D Billy Sweezey.) |
| | G | Waived (The Boston bruins waived G Brandon Bussi.) |
| | LW | Waived (The Boston Bruins waived F Jeffrey Viel.) |
| | G | Waived (The Boston bruins waived G Jiri Patera.) |
| | G | Called up from minors (The Boston Bruins recalled G Kasimir Kaskisuo from the minors.) |
| | D | Called up from minors (The Boston Bruins recalled D Michael Callahan from the minors.) |
| | D | Called up from minors (The Boston Bruins recalled D Jackson Edward from the minors.) |
| | C | Called up from minors (The Boston Bruins recalled F Jaxon Nelson from the minors.) |
| | C | Called up from minors (The Boston Bruins recalled F Brett Harrison from the minors.) |
| | C | Called up from minors (The Boston Bruins recalled F Georgii Merkulov from the minors.) |
| | C | Called up from minors (The Boston Bruins recalled F Riley Duran from the minors.) |
| | G | Called up from minors (The Boston Bruins recalled G Ryan Bischel from the minors.) |
| | G | Waived (The Boston Bruins waived G Michael DiPietro.) |
| | C | Waived (The Boston Bruins waived F Vinni Lettieri.) |
| | D | Waived (The Boston Bruins waived D Jordan Oesterle.) |
| | RW | Called up from minors (The Boston Bruins recalled F Fabian Lysell from the minors.) |
| | G | Claimed (The Boston Bruins claimed G Jiri Patera off waivers from the Vancouver Canucks.) From |
| | RW | Sent to minors (The Boston Bruins sent F Fabian Lysell to the minors.) |
| | D | Sent to minors (The Boston bruins sent D Ryan Mast to the minors.) |
| | C | Waived (The Boston Bruins waived F Marc McLaughlin.) |
| | | Sent to minors (The Boston Bruins sent D Drew Bavaro to the minors.) |
| | C | Sent to minors (The Boston Bruins sent F Georgii Merkulov to the minors.) |
| | G | Sent to minors (The Boston Bruins sent G Ryan Bischel to the minors.) |
| | C | Sent to minors (The Boston Bruins sent F Jaxon Nelson to the minors.) |
| | D | Sent to minors (The Boston Bruins sent D Michael Callahan to the minors.) |
| | C | Sent to minors (The Boston Bruins sent F Adam Mechura to the minors.) |
| | D | Sent to minors (The Boston Bruins sent D Frederic Brunet to the minors.) |
| | C | Waived (The Boston Bruins waived F Marc McLaughlin.) |
| | D | Sent to minors (The Boston Bruins sent D Jackson Edward to the minors.) |
| | C | Sent to minors (The Boston Bruins sent F Brett Harrison to the minors.) |
| | C | Sent to minors (the Boston Bruins sent F John Farinacci to the minors.) |
| | G | Sent to minors (The Boston Bruins sent G Kasimir Kaskisuo to the minors.) |
| | LW | Sent to minors (the Boston Bruins sent F Joseph Abate to the minors.) |
| | G | Sent to minors (The Boston Bruins sent G Nolan Maier to the minors.) |
| | C | Sent to minors (The Boston bruins sent F Trevor Kuntar to the minors.) |
| | C | Sent to minors (The Boston bruins sent F Riley Duran to the minors.) |
| | D | Sent to minors (The Boston Bruins sent D Mason Millman to the minors.) |
| | D | Sent to minors (The Boston Bruins assigned D Loke Johansson to the minors.) |
| | C | Signed (The Boston Bruins signed F Tyler Johnson to a professional tryout agreement.) |
| | C | Activated (The Boston Bruins activated F Matthew Poitras.) |
| | C | Released (The Boston Bruins released F Oskar Steen.) |
| | D | Signed (The Boston Bruins signed D Alec Regula to a two-way contract.) |
| | LW | Signed (The Boston Bruins signed F Max Jones to a standard contract.) |
| | LW | Signed (The Boston Bruins signed F Cole Koepke to a two-way contract.) |
| | LW | Signed (The Boston Bruins signed F Jeffrey Viel.) |
| | D | Signed (The Boston Bruins signed D Billy Sweezey to a two-way contract.) |
| | LW | Signed (The Boston Bruins signed F Riley Tufte to a standard contract.) |
| | C | Signed (The Boston Bruins signed F Elias Lindholm to a standard contract.) |
| | D | Signed (The Boston Bruins signed D Nikita Zadorov to a standard contract.) |
| | D | Signed (The Boston Bruins signed D Jordan Oesterle to a two-way contract.) |
| | LW | Became Unrestricted Free Agent (F Pat Maroon elected free agency.) |
| | C | Became Unrestricted Free Agent (F Jesper Boqvist declared free agency.) |
| | LW | Became Unrestricted Free Agent (F Milan Lucic elected free agency.) |
| | LW | Became Unrestricted Free Agent (F James van Riemsdyk elected free agency.) |
| | D | Became Unrestricted Free Agent (D Derek Forbort elected free agency.) |
| | D | Became Unrestricted Free Agent (D Kevin Shattenkirk elected free agency.) |
| | D | Drafted (The Boston Bruins drafted D Elliott Groenewold) |
| | C | Traded (The Boston Bruins traded F Jakub Lauko to the Minnesota Wild) To |
| | C | Drafted (The Boston Bruins drafted C Jonathan Morello) |
| | LW | Became Unrestricted Free Agent (F Danton Heinen elected free agency.) |
| | C | Traded (The Minnesota Wild traded F Vinni Lettieri to the Boston Bruins) From |
| | C | Became Unrestricted Free Agent (F Jayson Megna elected free agency.) |
| | D | Drafted (The Boston Bruins drafted D Loke Johansson.) |
| | D | Became Unrestricted Free Agent (D Matt Grzelcyk elected free agency.) |
| | C | Became Unrestricted Free Agent (F Anthony Richard elected free agency.) |
| | LW | Became Unrestricted Free Agent (F Jake DeBrusk elected free agency.) |
| | D | Became Unrestricted Free Agent (D Dan Renouf elected free agency.) |
| | C | Drafted (The Boston Bruins drafted F Dean Letourneau.) |
| | G | Signed (The Boston Bruins signed G Brandon Bussi to a one-year, two-way contract.) |
| | C | Traded (The Boston Bruins acquired F Mark Kastelic in a trade.) From |
| | G | Traded (The Boston Bruins acquired G Joonas Korpisalo in a trade.) From |
| | G | Traded (The Ottawa Senators acquired G Linus Ullmark in a trade.) To |
| | D | Signed (The Boston Bruins signed D Ian Mitchell.) |
| | C | Called up from minors (The Boston Bruins recalled F Georgii Merkulov from the minors.) |
| | LW | Called up from minors (The Boston Bruins recalled F Joseph Abate from the minors.) |
| | G | Called up from minors (The Boston Bruins recalled G Michael DiPietro from the minors.) |
| | D | Called up from minors (The Boston Bruins recalled D Ian Mitchell from the minors.) |
| | C | Called up from minors (The Boston Bruins recalled F Oskar Steen from the minors.) |
| | C | Called up from minors (The Boston Bruins recalled F Trevor Kuntar from the minors.) |
| | D | Called up from minors (The Boston Bruins recalled D Michael Callahan from the minors.) |
| | G | Called up from minors (The Boston Bruins recalled G Brandon Bussi from the minors.) |
| | G | Sent to minors (The Boston Bruins assigned G Michael DiPietro to the minors.) |
| | C | Called up from minors (The Boston Bruins recalled F Jayson Megna from the minors.) |
| | C | Called up from minors (The Boston Bruins recalled F Patrick Brown from the minors.) |
| | C | Sent to minors (The Boston Bruins sent F Patrick Brown to the minors.) |
| | C | Called up from minors (The Boston Bruins recalled F Patrick Brown from the minors.) |
| | G | Called up from minors (The Boston Bruins recalled G Michael DiPietro from the minors.) |
| | D | Called up from minors (The Boston Bruins recalled D Mason Lohrei from the minors.) |
| | D | Called up from minors (The Boston Bruins recalled D Derek Forbort from the minors.) |