CPT code 84597: Vitamin K assay2026 Medicare lab fee · Clinical Laboratory Fee Schedule
Measures vitamin K level for laboratory assessment of vitamin K status when the specifically measured analyte is vitamin K.
Medicare pays $13.72 for 84597 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
$13.72
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 84597 covers
84597 identifies a laboratory assay that measures vitamin K level. Select it when vitamin K is the analyte being measured, rather than a different vitamin or a general vitamin assay. The assay reports vitamin K, not coagulation time. Clinicians use the result in evaluating vitamin K status.
Report 84597 when the assay measures vitamin K. Medicare pays the test under the CLFS at one national amount, with the same payment across states and localities and no geographic adjustment or office-versus-facility difference. The 2026 national CLFS amount is $13.72, unchanged from 2020 through 2026. The test is excluded from the physician fee schedule by statute and is paid only through the CLFS.
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 84597
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 84597. 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 84597 with status X (excluded by statute), so the test itself is paid only from the CLFS.
84597 on the lab fee schedule since 2020
84597 · CLFS 2026 Q4 (current)
$13.72
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.
84597 compared with similar tests
- 84590Vitamin A$11.61
- 84590 measures vitamin A; 84597 measures vitamin K.
- 84591Vitamin assayVitamin not otherwise specified$17.06
- 84591 applies to a vitamin assay without a more specific vitamin code. Use 84597 when the measured vitamin is K.
- 85610Prothrombin timeRoutine coagulation test$4.29
- 85610 measures prothrombin time, not vitamin K level. The tests measure different things and may be ordered together.
84597 billing questions
When should 84597 be reported instead of 84591?
Use 84597 when the assay measures vitamin K specifically. Code 84591 applies to a vitamin assay when no more specific vitamin code describes the test.
Is 84597 a coagulation test?
No. It measures vitamin K level, not coagulation time. Prothrombin time testing, such as 85610, measures coagulation time.
Does Medicare pay 84597 under the physician fee schedule?
No. Medicare pays 84597 through the CLFS; the test is excluded from the physician fee schedule by statute.
Does the CLFS payment vary by locality or setting?
No. The national CLFS amount applies across states and localities, with no geographic adjustment or office-versus-facility difference.
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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