Clinical Laboratory Fee Schedule (CLFS) and PAMA Guide
Updated Oct 30, 2026
The Clinical Laboratory Fee Schedule (CLFS) is the Medicare Part B payment schedule for most clinical diagnostic laboratory tests (CDLTs). Under the Protecting Access to Medicare Act of 2014 (PAMA), CMS sets each rate from the weighted median of private-payor rates that applicable laboratories report. CMS publishes the schedule as quarterly downloadable files on its CLFS Files page.
2026 status at a glance
According to CMS's CLFS page, Section 6226 of the Consolidated Appropriations Act, 2026 (enacted February 3, 2026) changed the PAMA timeline:
| Item | What CMS reports |
|---|---|
| Data collection period | January 1 – June 30, 2025 |
| Data reporting period | May 1 – July 31, 2026 (closed) |
| 2026 payment reduction | None (0% phase-in reduction) |
| 2027–2029 | Payment for a test may not drop by more than 15% per year compared with the prior year |
| Cycle going forward | Rates for CDLTs that aren't ADLTs are updated every 3 years |
Phase-in reduction caps by year
| Payment year | Data collection period | Reporting period | Reduction cap |
|---|---|---|---|
| 2020 | Jan 1 – Jun 30, 2016 | Jan 1 – May 30, 2017 | 10% |
| 2021–2026 | Jan 1 – Jun 30, 2016 | Jan 1 – May 30, 2017 | 0.0% |
| 2027 | Jan 1 – Jun 30, 2025 | May 1 – Jul 31, 2026 | 15% |
Source: CMS, Clinical Laboratory Fee Schedule.
Who reports under PAMA
CMS describes a three-step process. Labs collect applicable information, analyze whether they meet the majority-of-Medicare-revenues and low-expenditure thresholds, and then the reporting entity submits the data. The governing regulations are at 42 CFR Part 414, Subpart G. They define "applicable laboratory," "applicable information," and the reporting rules.
| Private payor type counted under PAMA | Counted? |
|---|---|
| Health insurance issuer | Yes |
| Group health plan | Yes |
| Medicare Advantage plan | Yes |
| Medicaid managed care organization | Yes |
Source: CMS CLFS page.
How to read the CMS CLFS file
The CY 2026 Q4 release (26CLABQ4) is a ZIP with CSV, TXT, XLSX, and a PDF record layout. CMS lists it as updated for October 2026 under CR 14569.
| Column | Meaning |
|---|---|
| YEAR | Calendar year of the schedule |
| HCPCS | CPT or HCPCS Level II code |
| MOD | Modifier (for example, QW for waived tests) |
| EFF_DATE | Effective date of the rate |
| INDICATOR | National or local pricing indicator |
| RATE | Payment amount for the code |
| Descriptors | AMA-copyrighted CPT descriptors (license required for reuse) |
Sample CY 2026 Q4 amounts
| Code | Test (paraphrased) | Amount |
|---|---|---|
| 36415 | Venipuncture collection | $9.34 |
| 80053 | Comprehensive metabolic panel | $10.56 |
| 80061 | Lipid panel | $13.39 |
| 84443 | TSH | $16.80 |
| 85025 | CBC with automated differential | $7.77 |
| 87491 | Chlamydia, amplified probe | $35.09 |
| 87591 | Gonorrhea, amplified probe | $35.09 |
| G0480 | Definitive drug testing, 1–7 drug classes | $114.43 |
All from 26CLABQ4. A listed amount doesn't mean Medicare covers the test.
What this means for lab operations
Payment amounts for 2027 depend on the private-payor data reported in 2026. That means accurate payer-rate records, test menus, and CLIA documentation matter for both billing and audits. myLabCompliance gives lab directors and compliance teams one system for test menus, QC, personnel, and document control. With it, your operational records hold up when payment rules change.
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FAQs
What is the CLFS?
It is the Medicare Part B fee schedule that sets payment for most clinical diagnostic laboratory tests. CMS publishes it quarterly.
How does PAMA set CLFS rates?
CMS uses the weighted median of private-payor rates that applicable laboratories report during a data collection period.
When was the most recent PAMA reporting period?
May 1 – July 31, 2026, using data from January 1 – June 30, 2025, according to CMS.
Will CLFS rates be cut in 2026?
CMS states that there is no phase-in reduction in 2026.
What happens in 2027–2029?
Payment for a test may not be reduced by more than 15% per year compared with the prior year's amount.
Which private payors count?
Health insurance issuers, group health plans, Medicare Advantage plans, and Medicaid managed care organizations.
Where do I download the current CLFS?
From the CMS CLFS Files page. The current release is 26CLABQ4.
Does a CLFS amount guarantee coverage?
No. CMS notes that including a code or amount doesn't imply Medicare covers the test.
Sources
- CMS, Clinical Laboratory Fee Schedule: https://www.cms.gov/medicare/payment/fee-schedules/clinical-laboratory-fee-schedule-clfs
- CMS, CLFS Files (26CLABQ4): https://www.cms.gov/medicare/payment/fee-schedules/clinical-laboratory-fee-schedule-clfs/files
- eCFR, 42 CFR Part 414 Subpart G: https://www.ecfr.gov/current/title-42/chapter-IV/subchapter-B/part-414/subpart-G
- AMA, CPT: https://www.ama-assn.org/practice-management/cpt