CPT code 87340: HBsAg test, surface antigen immunoassay2026 Medicare lab fee · Clinical Laboratory Fee Schedule
An immunoassay for hepatitis B surface antigen, reported when screening for or evaluating possible hepatitis B infection.
Medicare pays $10.33 for 87340 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
$10.33
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 87340 covers
87340 detects hepatitis B surface antigen (HBsAg) in a blood specimen using an immunoassay, with a qualitative or semiquantitative result. It is used in screening and evaluation for hepatitis B and may be ordered by clinicians assessing suspected infection or a patient's hepatitis status. Laboratories and office-based practices report the assay. A detected HBsAg result identifies the marker but does not, by itself, distinguish acute from chronic infection.
Report 87340 for the HBsAg detection assay. When a separate neutralization test is performed to confirm HBsAg, report 87341 for that service; the neutralization test is distinct from the detection assay. Medicare pays 87340 through the CLFS, with one national amount applying in every state and locality and no office-versus-facility difference. The 2026 national CLFS amount is $10.33, unchanged from 2020 through 2026. The test 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 87340
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 87340. 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 87340 with status X (excluded by statute), so the test itself is paid only from the CLFS.
87340 on the lab fee schedule since 2020
87340 · CLFS 2026 Q4 (current)
$10.33
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.
87340 compared with similar tests
- 87341HBsAg confirmationNeutralization assay$10.33
- 87340 detects HBsAg by immunoassay; 87341 is a separate neutralization test used to confirm HBsAg.
- 87350HBeAg testImmunoassay antigen detection$11.53
- 87350 detects hepatitis B e antigen, a different viral marker. Use 87340 for surface antigen detection.
- 86706Surface antibodyHepatitis B$10.74
- 86706 detects antibody to hepatitis B surface antigen, not the surface antigen itself.
- 86704Core antibodyTotal antibody$12.05
- 86704 detects hepatitis B core antibody; 87340 detects hepatitis B surface antigen.
87340 billing questions
When should 87340 be reported instead of 87341?
Report 87340 for the HBsAg detection immunoassay. Report 87341 when a separate neutralization test is performed to confirm HBsAg.
Does 87340 detect hepatitis B antibodies?
No. It detects surface antigen. Surface antibody testing is reported with 86706, and core antibody testing with 86704.
Can a positive 87340 result distinguish acute from chronic infection?
No. A detected result shows HBsAg is present, but 87340 alone does not determine whether infection is acute or chronic.
How does Medicare pay for 87340?
Medicare pays the test through the CLFS. The same national amount applies in every locality and in office and facility settings.
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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