Is there a written guideline that specifically states "you can't bill patients different amounts for services received based on insurance or financial ability to pay"? This is repeated statement in the billing field. I am seeking a statement in writing to support this issue. My example is 2 different patients receive the same 2 exact services. 1 patient is covered under BCBS with a copay and 1 patient is a self pay patient. The physician wants to only bill the self pay patient for 1 service due to financial constraints. Is this legal?