Cubs Roster & Staff
Transactions
| Date | Transaction |
| 09/30/21 | Chicago Cubs selected the contract of C Erick Castillo from Iowa Cubs. |
| 09/30/21 | Chicago Cubs placed C Austin Romine on the 10-day injured list. |
| 09/29/21 | Chicago Cubs placed 3B Patrick Wisdom on the 10-day injured list. |
| 09/29/21 | Chicago Cubs selected the contract of 2B Trent Giambrone from Iowa Cubs. |
| 09/28/21 | Chicago Cubs recalled RHP Jason Adam from Iowa Cubs. |
| 09/28/21 | Chicago Cubs placed RHP Keegan Thompson on the 10-day injured list. Right shoulder inflammation. |
| 09/25/21 | Chicago Cubs optioned RHP Jason Adam to Iowa Cubs. |
| 09/24/21 | Chicago Cubs selected the contract of RHP Jason Adam from Iowa Cubs. |
| 09/24/21 | Chicago Cubs placed C Robinson Chirinos on the 10-day injured list. Left oblique strain. |
| 09/24/21 | Chicago Cubs recalled 1B Greg Deichmann from Iowa Cubs. |
| 09/21/21 | Chicago Cubs placed 1B Alfonso Rivas on the 10-day injured list. Right middle finger tendon injury. |
| 09/21/21 | Chicago Cubs sent RHP Dillon Maples outright to Iowa Cubs. |
| 09/21/21 | Chicago Cubs placed RF Jason Heyward on the 10-day injured list. Concussion. |
| 09/21/21 | Chicago Cubs recalled LF Nick Martini from Iowa Cubs. |
| 09/19/21 | Chicago Cubs activated RHP Keegan Thompson from the 10-day injured list. |
| 09/19/21 | Chicago Cubs designated RHP Dillon Maples for assignment. |
| 09/19/21 | Chicago Cubs activated 2B Nico Hoerner. |
| 09/19/21 | Chicago Cubs optioned LF Nick Martini to Iowa Cubs. |
| 09/17/21 | Chicago Cubs activated LHP Adam Morgan from the bereavement list. |
| 09/17/21 | Chicago Cubs placed RHP Manuel Rodriguez on the 10-day injured list. Right shoulder inflammation. |
| 09/14/21 | Chicago Cubs selected the contract of RF Trayce Thompson from Iowa Cubs. |
| 09/14/21 | Chicago Cubs placed RF Michael Hermosillo on the 60-day injured list. Left forearm strain. |
| 09/14/21 | Chicago Cubs placed RF Jason Heyward on the 7-day injured list. Concussion. |
| 09/12/21 | Chicago Cubs placed RF Jason Heyward on the 7-day injured list. Concussion. |
| 09/12/21 | Chicago Cubs placed RF Jason Heyward on the 7-day injured list. Concussion. |
| 09/12/21 | Chicago Cubs sent 2B Nico Hoerner on a rehab assignment to Iowa Cubs. |
| 09/10/21 | Chicago Cubs recalled RHP Tommy Nance from Iowa Cubs. |
| 09/10/21 | Chicago Cubs signed free agent RHP Jackson McClelland to a minor league contract. |
| 09/10/21 | Chicago Cubs placed LHP Adam Morgan on the bereavement list. |
| 09/08/21 | Chicago Cubs selected the contract of LF Nick Martini from Iowa Cubs. |
| 09/08/21 | Chicago Cubs sent SS Andrew Romine outright to Iowa Cubs. |
| 09/08/21 | Chicago Cubs placed RF Michael Hermosillo on the 10-day injured list. Left forearm strain. |
| 09/07/21 | Chicago Cubs sent RHP Jonathan Holder on a rehab assignment to Iowa Cubs. |
| 09/06/21 | Chicago Cubs designated SS Andrew Romine for assignment. |
| 09/06/21 | Chicago Cubs activated 2B David Bote from the 10-day injured list. |
| 09/04/21 | Chicago Cubs placed RHP Keegan Thompson on the 10-day injured list. Right shoulder inflammation. |
| 09/04/21 | Chicago Cubs activated C Willson Contreras. |
| 09/01/21 | Chicago Cubs activated RHP Adbert Alzolay. |
| 09/01/21 | Chicago Cubs activated RHP Dillon Maples. |
| 09/01/21 | Chicago Cubs activated RHP Adbert Alzolay. |
| 09/01/21 | Chicago Cubs activated RHP Adbert Alzolay. |