Doesn’t Medicare pay for all laboratory testing?

No, while Medicare rules allow payments for most procedures, a few categories are not covered and will result in a bill to the patient. Categories not covered by Medicare include:

• Screening procedures: Procedures that might be ordered as part of a routine exam (for example, yearly physical) are in most cases not covered.
• Items not medically necessary: For some procedures, Medicare maintains a list of diagnoses (reasons for testing) for which they will pay for the particular test. If your particular diagnosis is not on this list, Medicare will not pay.
• Investigational tests: Tests that are not yet approved by the FDA are considered experimental or investigational and are never covered by Medicare.