CPT code 81509: Prenatal screen, three-protein algorithm2026 Medicare lab fee · Clinical Laboratory Fee Schedule
Maternal-serum biochemical screening using PAPP-A, hCG, and dimeric inhibin A to generate an algorithmic fetal congenital-abnormality risk score.
Medicare pays $1,487.37 for 81509 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
$1,487.37
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 81509 covers
This prenatal laboratory screen measures PAPP-A, hCG in any form, and dimeric inhibin A in maternal serum. An algorithm combines the results into a risk score for fetal congenital abnormalities; it is a screening assessment, not a diagnostic confirmation. Obstetric clinicians may order it as part of prenatal risk evaluation, with testing and score reporting performed by a clinical laboratory.
Report the service for the three-protein algorithm and its resulting risk score. Medicare pays it only under the CLFS, with one national amount across localities and no office-versus-facility payment difference. The 2026 national CLFS amount is $1,487.37, unchanged from 2020 through 2026. The test is excluded from the physician fee schedule and paid 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 81509
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 81509. 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 81509 with status X (excluded by statute), so the test itself is paid only from the CLFS.
81509 on the lab fee schedule since 2020
81509 · CLFS 2026 Q4 (current)
$1,487.37
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.
81509 compared with similar tests
- 81508Prenatal Risk AssayTwo Serum Proteins$54.30
- This code represents the three-protein maternal-serum algorithm. 81508 is the related two-protein version.
- 81510Triple screenAFP, uE3, and hCG$55.54
- 81510 is a related three-analyte fetal-risk code. Choose between these codes based on the biochemical assay and algorithm performed.
- 81507Trisomy screeningTrisomies 21, 18, and 13$795.00
- 81507 addresses fetal aneuploidy and trisomy risk. This code reports a maternal-serum biochemical algorithm for fetal congenital-abnormality risk.
81509 billing questions
Which specimen and markers identify this test?
It uses maternal serum to measure PAPP-A, hCG in any form, and dimeric inhibin A. The results feed an algorithm that reports a fetal congenital-abnormality risk score.
How does this differ from 81508?
81508 represents a related two-protein screen. Use 81509 when the laboratory performs the three-protein algorithm described by this code.
How does this differ from 81510?
81510 is a related three-analyte fetal-risk code. Select between the codes based on the biochemical assay and algorithm performed.
Is the reported risk score part of the laboratory service?
Yes. The service includes combining the biochemical assay results into an algorithmic risk score.
How does Medicare pay this service?
Medicare pays it under the CLFS using one national amount across states and localities, without an office or facility payment difference. The test is excluded from the physician fee schedule.
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
Fee sheets · Coming soon
Put 81509 and the rest of your codes on one sheet
Your codes at your locality, with payer contracts beside Medicare.
Join the waitlist