There are provided systems and methods for a credential storage manager for protecting credential security during delegated account use. A first user that controls the account may delegate usage of the account to a second user through a credential manager of a transaction process that manages sensitive authentication information and delegates account usage. The credential manager may automatically fill authentication information for use of the account by the second user. A device fingerprint of a device of the second user may be used to provide risk prevention and access the account. The credential manager may prevent revealing of the credentials and navigation to sensitive data or processes with the account. Two-factor authentication may be performed by receiving a code in a message received by a device of the first user, scraping the code from the message, and entering the code to a device of the second user.