CPT code 84182: Western blot, immunological band identification2026 Medicare lab fee · Clinical Laboratory Fee Schedule
Immunological-probe western blot testing identifies protein bands in blood or another body fluid and is reported for each test performed.
Medicare pays $29.21 for 84182 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
$29.21
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 84182 covers
This laboratory assay uses an immunological probe to identify protein bands in blood or another body fluid. The laboratory service includes band identification and a report, rather than simply measuring total protein concentration. Clinicians may order it when the diagnostic question calls for identifying a protein-band pattern; the laboratory reports findings from the specimen tested. Clinical laboratories perform the assay, and the ordering clinician uses the result with other diagnostic findings.
Report the test for each performance. Medicare pays the laboratory service under the CLFS; the 2026 national amount is $29.21, unchanged from 2020 through 2026. The same amount applies in every state and locality, without an office or facility payment difference. A separate physician interpretation is payable under the physician fee schedule when billed with modifier 26; this is distinct from the laboratory report.
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 84182
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 84182. 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 84182 with status X (excluded by statute), so the test itself is paid only from the CLFS.
Physician interpretation (modifier 26)
A physician’s interpretation is billed separately with modifier 26 and paid under the physician fee schedule: $17.70 nationally in the office, before locality adjustment.
84182 on the lab fee schedule since 2020
84182 · CLFS 2026 Q4 (current)
$29.21
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.
84182 compared with similar tests
- 84181Western blotInterpretation and report$17.03
- Both are western blot codes. 84182 specifies protein band identification using an immunological probe; select the code that matches the service documented and its applicable descriptor.
- 84165Protein electrophoresisSerum fractionation and quantitation$10.74
- 84165 evaluates serum protein fractions by electrophoresis. Use 84182 when the service is a protein western blot with immunological band identification.
- 84166Protein electrophoresisUrine or CSF$17.83
- 84166 is electrophoresis for urine or cerebrospinal fluid proteins. 84182 is for western blot band identification in blood or another body fluid.
84182 billing questions
How does 84182 differ from 84181?
84182 identifies protein as the subject of the western blot and specifies immunological band identification. For 84181, compare the documented service with that code’s applicable descriptor rather than treating the neighboring codes as interchangeable.
How many units should be reported?
Report the service for each test performed. The code describes testing each blood or other body fluid specimen.
Can a physician interpretation be billed separately?
A separate physician interpretation is payable under the physician fee schedule with modifier 26. The laboratory service also includes its report.
How does Medicare pay for the laboratory test?
Medicare pays the test under the CLFS at one national amount that applies across localities, with no office or facility payment difference.
What documentation supports reporting 84182?
Document the blood or other body fluid tested and the western blot service with immunological identification of protein bands. Retain the laboratory report supporting the test performed.
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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