- Post-pay: Client/University invoiced on a monthly basis for tests delivered during previous month.
- Purchase Order:Client/University designates number of test units Castle is approved to deliver. Castle invoices on a monthly basis for the tests delivered against the purchase order.
- Pre-pay: Client/University submits prepayment by check for a designated number of exam units.
- E-commerce: Students who test off campus through Castle's sites or Live Online Proctoring can pay via debit card or credit card at the time of scheduling.
NOTE: No refunds are permitted for purchased exam units.