CPT code 84432: Thyroglobulin, serum tumor marker2026 Medicare lab fee · Clinical Laboratory Fee Schedule
Measures thyroglobulin, a protein made by thyroid follicular cells, often to monitor for residual or recurrent differentiated thyroid cancer after treatment.
Medicare pays $16.06 for 84432 under the 2026 Clinical Laboratory Fee Schedule: one national amount, the same in every state and setting.
Medicare lab fee · CLFS 2026 Q4
National CLFS amount
$16.06
In effect since Jan 1, 2026. The same amount in every state, payment locality and setting.
- Geographic adjustment
- None
- Office vs facility
- Same
- Since 2020
- Unchanged
- CMS updates
- Quarterly
Medicare pays the lesser of the lab’s charge and this amount. Patients usually owe no Part B deductible or coinsurance for covered clinical lab tests.
On this page 8 sections
What 84432 covers
The assay measures thyroglobulin, a protein produced by thyroid follicular cells. Clinicians most often use it as a tumor marker when monitoring patients treated for differentiated thyroid cancer, including after thyroidectomy or radioactive iodine therapy. The test is typically performed on a blood specimen in a clinical laboratory and may be ordered by endocrinologists, oncologists, or other clinicians managing thyroid cancer. Thyroglobulin antibody testing can help assess whether antibodies may affect interpretation of the result.
Report one unit for the thyroglobulin assay performed. Medicare pays this test only through the CLFS. The 2026 national CLFS amount is $16.06, unchanged since 2020. The same amount applies in every state and locality, without geographic or office-versus-facility adjustment. The test has no separate physician fee schedule payment.
This summary was written with AI assistance from CMS Clinical Laboratory Fee Schedule data. Amounts on this page come directly from CMS files.
How Medicare pays 84432
Clinical lab tests aren’t priced like physician services. They’re paid from their own fee schedule, with its own rules. See the whole lab fee schedule.
One national amount
CMS sets a single Clinical Laboratory Fee Schedule amount for 84432. There’s no geographic (GPCI) adjustment, so it pays the same in every state and payment locality.
No office or facility rate
Lab tests aren’t built from relative value units, so there’s no office and facility split: the place of service doesn’t change the CLFS amount.
Updated every quarter
CMS republishes the CLFS each quarter. New tests, often proprietary laboratory analyses (PLA codes), join during the year; existing amounts are updated each January.
Excluded from the physician fee schedule
The physician fee schedule lists 84432 with status X (excluded by statute), so the test itself is paid only from the CLFS.
84432 on the lab fee schedule since 2020
84432 · CLFS 2026 Q4 (current)
$16.06
Unchanged since Jan 1, 2020
27 quarterly CLFS releases on file, first CLFS 2020 Q1. A code missing from a quarter wasn’t on that release.
84432 compared with similar tests
- 86800Thyroid antibodyThyroglobulin-specific antibody$15.91
- Code 86800 measures thyroglobulin antibodies, not thyroglobulin itself. It may be performed with 84432 to help assess potential antibody interference.
- 84443TSH testThyroid-stimulating hormone$16.80
- Code 84443 measures thyroid-stimulating hormone. It evaluates thyroid regulation rather than serving as a thyroglobulin tumor-marker assay.
- 84439Free T4Unbound thyroxine$9.02
- Code 84439 measures free thyroxine, a circulating thyroid hormone. Use 84432 for measurement of thyroglobulin.
- 84436Total T4Total thyroxine$6.87
- Code 84436 measures total thyroxine, not thyroglobulin. The assays address different analytes and clinical questions.
84432 billing questions
When should 84432 be reported instead of a thyroid hormone test?
Report 84432 when the laboratory measures thyroglobulin, commonly for thyroid cancer monitoring. TSH, T3, and T4 codes represent different analytes used to assess thyroid function.
Is thyroglobulin antibody testing included?
No. Thyroglobulin antibody measurement is a separate assay, reported with 86800 when performed.
How many units should be reported?
Report one unit for each thyroglobulin assay performed.
Can 84432 be reported with TSH testing?
Yes, when both tests are ordered and performed for their distinct purposes. Thyroglobulin can support thyroid cancer monitoring, while TSH evaluates thyroid function or treatment status.
How does Medicare pay for 84432?
Medicare pays the test through the CLFS at one national amount, with no locality or office-versus-facility adjustment. There is no separate physician fee schedule payment.
Where this amount comes from
FeeBase reads lab amounts directly from the CMS Clinical Laboratory Fee Schedule file for the quarter: one row per code, with its payment indicator and national amount. Contractor-priced tests are labeled, never given a made-up amount. Amounts are Medicare payment limits, not a patient’s bill or a commercial rate.
CMS CLFS 2026 Q4 · effective Oct 1, 2026 through the day before Jan 1, 2027
Show the CMS file line behind this amount
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