The Days Payable Outstanding Calculator was created to allow the AP Department to see how adjustments to the number of days that vendor invoices are outstanding prior to payment impact cash flow. Many companies have a policy for payment terms for each vendor. Payment terms might be specific to a vendor contract or a general policy governing when an invoice will be paid based on the date of receipt. Changing the number of days it takes for your company to process a vendor payment will directly impact company cash flow and cash position.