Lenders and secured creditors often require that debtor-customers direct all receivable collections into a lockbox, hoping to wrangle any available proceeds to apply to their debtors’ outstanding debt. In requiring a debtor or its customer to remit payments to a lockbox, however, creditors may be overlooking a potential source of significant liability. A creditor using a lockbox may unwittingly expose itself to greater risk and liability than just a debtor’s default if it receives funds that were collected as sales tax on a debtor’s goods or services.