When bank customers undergo a major institutional transition or account migration, the destination bank depends entirely on the specific merger, acquisition, or partnership agreement announced by their original provider. For example, when smaller regional institutions or fintech platforms undergo portfolio sales, customer accounts are systematically migrated to the acquiring chartered partner bank. Affected account holders receive comprehensive legal notifications detailing the target transition bank, new routing numbers, updated digital login procedures, and instructions regarding debit card replacements well in advance of the final conversion date.