Cubs Roster & Staff
Transactions
| Date | Transaction |
| 08/31/18 | Chicago Cubs recalled RHP Dillon Maples from Iowa Cubs. |
| 08/31/18 | Chicago Cubs placed RF Jason Heyward on the 10-day disabled list. Right hamstring tightness. |
| 08/30/18 | Chicago Cubs sent LHP Drew Smyly on a rehab assignment to South Bend Cubs. |
| 08/30/18 | RHP James Norwood returned to Iowa Cubs from Chicago Cubs. |
| 08/30/18 | Chicago Cubs optioned RHP Alec Mills to Iowa Cubs. |
| 08/30/18 | Minnesota Twins traded C Bobby Wilson to Chicago Cubs for C Chris Gimenez and Player To Be Named Later. |
| 08/30/18 | Minnesota Twins traded C Bobby Wilson to Chicago Cubs for C Chris Gimenez and Player To Be Named Later. |
| 08/30/18 | Chicago Cubs activated LHP Mike Montgomery from the 10-day injured list. |
| 08/30/18 | Chicago Cubs designated RHP Cory Mazzoni for assignment. |
| 08/29/18 | Chicago Cubs recalled James Norwood from Iowa Cubs. |
| 08/27/18 | Chicago Cubs sent 3B Kris Bryant on a rehab assignment to Iowa Cubs. |
| 08/27/18 | Chicago Cubs sent RHP Tyler Chatwood on a rehab assignment to Iowa Cubs. |
| 08/24/18 | Chicago Cubs optioned RHP Dillon Maples to Iowa Cubs. |
| 08/24/18 | Chicago Cubs recalled Alec Mills from Iowa Cubs. |
| 08/24/18 | Chicago Cubs sent LHP Brian Duensing on a rehab assignment to Iowa Cubs. |
| 08/23/18 | Chicago Cubs recalled Dillon Maples from Iowa Cubs. |
| 08/23/18 | Chicago Cubs placed RHP Tyler Chatwood on the 10-day disabled list retroactive to August 20, 2018. Left hip tightness. |
| 08/22/18 | Chicago Cubs activated 2B Daniel Murphy. |
| 08/22/18 | Chicago Cubs placed SS Addison Russell on the 10-day disabled list retroactive to August 20, 2018. Sprained left middle finger. |
| 08/21/18 | Washington Nationals traded 2B Daniel Murphy to Chicago Cubs for 2B Andruw Monasterio and Player To Be Named Later. |
| 08/21/18 | Washington Nationals traded 2B Daniel Murphy to Chicago Cubs for 2B Andruw Monasterio and Player To Be Named Later. |
| 08/19/18 | Chicago Cubs sent RHP Yu Darvish on a rehab assignment to South Bend Cubs. |
| 08/17/18 | Chicago Cubs placed LHP Mike Montgomery on the 10-day disabled list retroactive to August 14, 2018. Left shoulder inflammation. |
| 08/17/18 | Chicago Cubs recalled Randy Rosario from Iowa Cubs. |
| 08/15/18 | Kansas City Royals traded LF Terrance Gore to Chicago Cubs for cash. |
| 08/14/18 | Chicago Cubs traded OF Alexander Ovalles to Texas Rangers. |
| 08/12/18 | Chicago Cubs sent RHP Anthony Bass outright to Iowa Cubs. |
| 08/10/18 | Chicago Cubs transferred RHP Yu Darvish from the 10-day disabled list to the 60-day disabled list. Right triceps tendonitis. |
| 08/10/18 | Chicago Cubs signed free agent LHP Jorge De La Rosa. |
| 08/10/18 | Chicago Cubs optioned LHP Randy Rosario to Iowa Cubs. |
| 08/09/18 | Chicago Cubs optioned LHP Randy Rosario to Iowa Cubs. |
| 08/06/18 | Chicago Cubs signed free agent RHP Yander Montero to a minor league contract. |
| 08/06/18 | Chicago Cubs signed free agent SS Rafael Morel to a minor league contract. |
| 08/06/18 | Chicago Cubs signed free agent OF Jose Lopez to a minor league contract. |
| 08/05/18 | Chicago Cubs sent RHP Anthony Bass on a rehab assignment to Iowa Cubs. |
| 08/03/18 | Chicago Cubs recalled Randy Rosario from Iowa Cubs. |
| 08/03/18 | Chicago Cubs placed LHP Brian Duensing on the 10-day disabled list. Left shoulder inflammation. |
| 08/01/18 | Chicago Cubs activated RHP Brandon Kintzler. |
| 08/01/18 | Chicago Cubs optioned LHP Randy Rosario to Iowa Cubs. |