MRF (Machine-Readable File)

Machine-Readable Files are the negotiated-rate and out-of-network-payment data files that health plans are required to publish monthly under the federal Transparency in Coverage rule that took effect July 2022. Every carrier and every self-funded plan must post two files: in-network rates for every provider, and out-of-network allowed amounts. The files are in JSON format, sit behind public URLs, and typically weigh in at hundreds of gigabytes per carrier per month.

This is genuinely new territory. Before 2022, negotiated rates were treated as trade secrets by carriers and providers alike, and price comparison was nearly impossible. The MRFs made every negotiated rate for every procedure at every facility public information for the first time. The catch: the files are so large and so unstructured that reading them requires specialized parsers and infrastructure. Consumer-facing price transparency tools exist because someone (companies like Turquoise Health, Serif Health, and TruePrice) built the parsing pipeline. The data quality is uneven — some carriers publish clean, complete files; others publish files with missing CPT codes, wrong provider identifiers, or stale rates.

The takeaway: MRFs are the foundation of the modern price transparency movement. If you're a self-funded employer, your TPA can access the underlying rates for your specific network — use them at renewal, at plan design, and at member steering decisions.