Medicare Part B covers medically necessary diagnostic laboratory tests ordered by a health care professional. Covered tests can include blood work used to investigate a suspected condition or monitor a diagnosed problem. Medicare also covers certain preventive tests, each with its own eligibility and timing rules.
Know why a test is being ordered
| Reason for testing | What to verify |
|---|---|
| Diagnosis or monitoring | Clinical need, order and the applicable test policy. |
| Preventive screening | Whether Medicare covers that screening and whether you meet its criteria. |
| Broad wellness package or self-requested panel | Which individual tests, if any, qualify; do not assume the package is covered. |
A yearly wellness visit does not automatically include every possible blood test. Frequency depends on the test, medical circumstances and coverage rules, rather than a blanket annual allowance.
Separate laboratory and other charges
You usually pay nothing for Medicare-covered diagnostic laboratory tests under Original Medicare. An office visit, imaging study or other service performed on the same day can have separate charges and different cost sharing. A bill containing several services should not be treated as a single laboratory charge.
Before testing, ask which laboratory will process the samples and whether it participates in Medicare. With Medicare Advantage, confirm the laboratory network and any authorization requirements.
Practical questions for the ordering office
- What is each test intended to evaluate?
- Is the order diagnostic or preventive?
- Does a timing or coverage rule apply?
- Will there be an office or other separate charge?
- Who will explain the results and follow-up?
If the provider expects a coverage problem, ask for the reason and any applicable written notice before a non-emergency service. The diagnosis and billing information must reflect your actual circumstances; choosing a code solely to obtain payment is inappropriate.
If a claim is denied
Compare the notice with the order and services received. Ask the office to correct genuine billing errors and review your appeal options. This article explains insurance coverage, without selecting tests, interpreting results or recommending treatment.
Related coverage questions
- Medicare Part B: Medical Coverage, Costs and Enrollment
- Medicare Coverage Database: How to Read NCDs and LCDs
- How to Find and Verify a Medicare Provider