Medical Billing Education – Form Use for Ambulatory Surgical Center Billing

Frequently, I am asked by students which form to use between the CMS-1500 form versus the UB-04 form. In most medical billing training programs, it is taught that inpatient billing uses the UB-04 form and outpatient billing uses the CMS-1500 form.  Ambulatory surgical centers are outpatient but are sort of hospital-like in nature, so this causes confusion.

Medical Billing Education – Form Use for Ambulatory Surgical Center Billing

In answering this question comprehensively, let’s talk about the main difference between the two forms. The UB-04 form is used for inpatient billing because there is more space on it and places to add in the numerous supplies used during a hospital stay.  Can you think of a time when you were in the hospital, and every time the nurse would bring a Q-tip, cotton swab, bed pan, etc. they would scan it onto your chart? I’m sure in looking at past hospital bills you wonder how a Band-Aid could cost $10. That $10 covers the supply such as a Band-Aid and the time it took a qualified nurse to get it, bring it to you, and to scan it onto your chart. :) Conversely, when you go to the doctor for a sore throat or other encounter, few supplies are used. Basically, billing entails a diagnosis or diagnoses, a procedure, and it’s done. So, the CMS-1500 form reflects the lesser complexity of this type of visit.

So, back to our original question, what form should ASCs use? The answer is both! :) An ASC that is attached to a hospital will most likely bill out on the UB-04 form. An ASC that is a free-standing facility will most likely use the CMS-1500 form. ASCs are usually used for less complex procedures so the CMS-1500 form can suffice. However, hospitals like to standardize everything, and so when an ASC is connected to a hospital it is likely they will use the UB-04 form instead.


By: Dawn Moreno, PhD, CBCS, CMAA, MTC. Lives in the beautiful Southwest United States and has been an instructor for medical coding/billing for the past 7 years.  Interested in quality medical billing training? Click Here for Medical Billing Education Courses

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