| Sep 24, 2021 |
 Carolina Hurricanes | Ronan Seeley | Signed to Standard Contract | |
 Calgary Flames | Jérémie Poirier | Signed to Entry-Level Contract | |
 Florida Panthers | Justin Sourdif | Signed to Entry-Level Contract | |
 Montreal Canadiens | Sami Niku | Signed to Standard Contract | ✔ |
 Winnipeg Jets | Nathan Beaulieu | Activated from LTIR | |
 San Jose Sharks | Matt Nieto | Activated from IR | |
 Ottawa Senators | Austin Watson | Activated from IR | |
 Columbus Blue Jackets | Boone Jenner | Activated from IR | |
| Columbus Blue Jackets | Zachary Werenski | Activated from IR | |
|
| Sep 23, 2021 |
 Colorado Avalanche | Erik Johnson | Activated from IR | |
| Colorado Avalanche | Pavel Francouz | Activated from IR | |
 Boston Bruins | John Moore | Activated from IR | |
|
| Sep 22, 2021 |
| Colorado Avalanche | Logan O'Connor | Signed to Standard Contract | |
 Philadelphia Flyers | Jon-Randall Avon | Signed to Entry-Level Contract | ✔ |
 Los Angeles Kings | Cal Petersen | Signed to Standard Contract | |
 Buffalo Sabres | Rasmus Dahlin | Signed to Standard Contract | |
|
| Sep 21, 2021 |
 St. Louis Blues | Robert Thomas | Signed to Standard Contract | |
 Minnesota Wild | Kirill Kaprizov | Signed to Standard Contract | |
| Columbus Blue Jackets | Elvis Merzlikins | Signed to Standard Contract | |
| Winnipeg Jets | Sami Niku | Contract terminated | |
| Winnipeg Jets | Sami Niku | Cleared waivers | |
|
| Sep 20, 2021 |
| Winnipeg Jets | Sami Niku | Placed on unconditional waivers | |
| Boston Bruins | Zach Senyshyn | Signed to Standard Contract | |
|
| Sep 19, 2021 |
 Vegas Golden Knights | Nolan Patrick | Signed to Standard Contract | |
|
| Sep 18, 2021 |
| Ottawa Senators | Logan Brown | Signed to Standard Contract | |
 Edmonton Oilers | Kailer Yamamoto | Signed to Standard Contract | |
|
| Sep 16, 2021 |
 Chicago Blackhawks | Nolan Allan | Signed to Entry-Level Contract | |
 New York Islanders | Cole Bardreau | Signed to Standard Contract | ✔ |
| New York Islanders | Otto Koivula | Signed to Standard Contract | |
| New York Islanders | Paul LaDue | Signed to Standard Contract | ✔ |
| New York Islanders | Dmytro Timashov | Signed to Standard Contract | ✔ |
| New York Islanders | Andy Andreoff | Signed to Standard Contract | ✔ |
| Vegas Golden Knights | Dylan Coghlan | Signed to Standard Contract | |
|
| Sep 14, 2021 |
 Detroit Red Wings | Givani Smith | Signed to Standard Contract | |
| Winnipeg Jets | Joona Luoto | Contract terminated | |
| Winnipeg Jets | Joona Luoto | Cleared waivers | |
| St. Louis Blues | Tyler Bozak | Signed to 35+ Contract | ✔ |
|
| Sep 13, 2021 |
| San Jose Sharks | Noah Gregor | Signed to Standard Contract | |
| Winnipeg Jets | Joona Luoto | Placed on unconditional waivers | |
|
| Sep 12, 2021 |
 Seattle Kraken | Ryan Donato | Signed to Standard Contract | ✔ |
| San Jose Sharks | Vladislav Kotkov | Contract terminated | |
| San Jose Sharks | Vladislav Kotkov | Cleared waivers | |
|
| Sep 11, 2021 |
| Edmonton Oilers | Cooper Marody | Signed to Standard Contract | |
| San Jose Sharks | Vladislav Kotkov | Placed on unconditional waivers | |
|
| Sep 10, 2021 |
| Calgary Flames | Michael Stone | Signed to Standard Contract | ✔ |
| Calgary Flames | Erik Gudbranson | Signed to Standard Contract | ✔ |
 Toronto Maple Leafs | Pontus Holmberg | Loan | |
|
| Sep 8, 2021 |
| Philadelphia Flyers | Morgan Frost | Activated from IR | |
| Calgary Flames | Connor Mackey | Signed to Standard Contract | |
| Calgary Flames | Brad Richardson | Signed to 35+ Contract | ✔ |
|
