The account number is essential for proper posting of payments to the correct account. If you have more than one account with the same vendors, it may be necessary to have separate vendor records for each account.
To keep this manageable, an easily identifiable naming convention is recommended, such as using the vendor name with the last 4 digits of the account for easy identification.
There are 2 accounts with AT&T for the same remit to address, Account #123456789 and Account #987654321. Create two (2) vendors and name them AT&T 6789 and AT&T 4321 respectively. The "Pay to" field should be AT&T, but the vendor names will be unique for each account number referenced and easily identifiable.