| 9/1/17 |
St. Louis Cardinals sent LHP Sean Gilmartin outright to Memphis Redbirds. |
| 9/1/17 |
St. Louis Cardinals signed free agent RHP Ronald Suarez to a minor league contract. |
| 9/1/17 |
St. Louis Cardinals signed free agent SS Luis Andujar to a minor league contract. |
| 9/1/17 |
St. Louis Cardinals signed free agent RHP Miguel Yedis to a minor league contract. |
| 9/1/17 |
St. Louis Cardinals signed free agent OF Diowill Burgos to a minor league contract. |
| 9/1/17 |
St. Louis Cardinals selected the contract of Jack Flaherty from Memphis Redbirds. |
| 9/1/17 |
St. Louis Cardinals selected the contract of C Alberto Rosario from Memphis Redbirds. |
| 9/1/17 |
St. Louis Cardinals selected the contract of RHP Sandy Alcantara from Springfield Cardinals. |
| 9/1/17 |
St. Louis Cardinals recalled Alex Mejia from Memphis Redbirds. |
| 9/1/17 |
St. Louis Cardinals recalled Harrison Bader from Memphis Redbirds. |
| 9/2/17 |
Philadelphia Phillies claimed LHP Kevin Siegrist off waivers from St. Louis Cardinals. |
| 9/2/17 |
St. Louis Cardinals signed free agent RHP Gabriel Contreras to a minor league contract. |
| 9/5/17 |
St. Louis Cardinals recalled Breyvic Valera from Memphis Redbirds. |
| 9/6/17 |
Philadelphia Phillies traded RHP Juan Nicasio to St. Louis Cardinals for 2B Eliezer Alvarez. |
| 9/11/17 |
St. Louis Cardinals optioned 2B Breyvic Valera to Memphis Redbirds. |
| 9/12/17 |
St. Louis Cardinals recalled RF Magneuris Sierra from Memphis Redbirds. |
| 9/13/17 |
St. Louis Cardinals activated 3B Jedd Gyorko from the 10-day disabled list. |
| 9/19/17 |
St. Louis Cardinals activated RHP Adam Wainwright from the 10-day disabled list. |
| 9/20/17 |
St. Louis Cardinals recalled Josh Lucas from Memphis Redbirds. |
| 9/20/17 |
St. Louis Cardinals recalled SS Aledmys Diaz from Memphis Redbirds. |
| 9/21/17 |
St. Louis Cardinals recalled Breyvic Valera from Memphis Redbirds. |
