If your account agreement does not address the process for removing an authorized signer, whether to require only a new signature card or to close the account and open a new one is a matter of bank policy. Given the concern about a former authorized signer using the account number after their removal, closing the account and opening a new one would mitigate that risk—as well as the risk of erroneously paying a check signed by the former authorized signer.
Additionally, whether you obtain the account owner’s written request for the removal of the authorized signer also is a matter of a bank policy, but we believe it would be prudent to do so. In the case of a joint account, we recommend using the same procedure to remove an authorized signer as was required to add the authorized signer. For example, if all joint account owners are required to provide written consent to add an authorized signer to the account, we recommend obtaining the written consent of all joint owners to remove an authorized signer. Conversely, if the written consent of only one joint account owner was sufficient to add an authorized signer to the account, a bank may consider removing an authorized signer with the written consent of only one joint owner.