Medicare payment for outpatient services provided in hospitals is based on set rates under Medicare Part B. The system for payment, known as the Outpatient Prospective Payment System (OPPS) is used when paying for services such as X-rays, emergency department visits, and partial hospitalization services in hospital outpatient departments. Payment for ambulatory surgical center (ASC) services is also based on rates set under Medicare Part B.
This system for payment is called the ASC Payment System and is used when paying for covered surgical procedures, including ASC facility services that are furnished in connection with the covered surgical procedure. CMS updates the OPPS/ASC regulations together in one rule annually, with comment periods open before the implementation of the final rule.