2025 Final Gapfill Rates Posted on CMS Website

CMS has released the final 2025 gapfill rates for Clinical Laboratory Fee Schedule (CLFS) codes following the public comment period earlier this year. A total of 34 codes were finalized, with approximately half receiving rate increases based on stakeholder-submitted pricing data and market feedback. Several molecular and PLA codes saw meaningful adjustments, including a plasma metagenomic test whose price increased from $36 to $444 in the final determination.

Gapfill rates apply when CMS is unable to crosswalk a new code to an existing CLFS test and instead relies on MAC-developed pricing based on resource costs, charges, and other market information. CMS will accept reconsideration requests for 30 days following publication.

The final rates can be found here: https://www.cms.gov/files/zip/2025-final-cms-determinations

What this means for providers:

Updated CLFS pricing affects allowable amounts, forecasting, and payor reimbursement alignment for 2025. Laboratories that believe a final rate undervalues actual cost or market data may submit reconsideration requests with supporting documentation.

Source: https://www.cms.gov/files/zip/2025-final-cms-determinations.zip