Generally, no transportation or transportation services ordered with a Government contractor issued charge card or charge account citation can be prepayment audited because the bank or charge card contractor pays the TSP directly, before your agency receives a bill that can be audited from the charge card company. However, if your agency contracts with the charge card or charge account provider to provide for a prepayment audit, then, as long as your agency is not liable for paying the bank for improper charges (as determined by the prepayment audit verification process), a prepayment audit can be used. As with all prepayment audit programs, the charge card prepayment audit must be approved by the GSA Audit Division prior to implementation. If the charge card contract does not provide for a prepayment audit, your agency must submit the transportation line items on the charge card to the GSA Audit Division for a postpayment audit.