Payment systems are part of the Control Procurement process in project management. As part of the bigger process that involves the monitoring and dissemination of payments to the seller, payment systems is defined as the provision and tracking of the invoices from the supplier. It is also a system that provides payment for the products and services rendered by the supplier thus the name.

It is important to take note that the payments to the sellers are usually processed using the accounts payable system of the buyer. Payment is only made once  there is a certification of satisfactory work provided by the authorized person (usually the project manager) from the project team.

The payment systems allow project managers to determine which deliverables have already been paid for. And since the system needs to be tracked and controlled, all payments made to all project management processes should be documented in accordance with the terms stipulated in the contract agreement.

The proper implementation of the payments system, along with the other tools of control procurement, can lead to different outputs such as change request, work performance information, and project document updates.