Data Sources

Sunlight Ledger presents data from four federal CMS datasets. All data is publicly available under the Freedom of Information Act. We aggregate and display the underlying records. Where noted, we apply categorical groupings (e.g., payment nature categories) to aid readability — these groupings are clearly labeled and do not alter the source data.

NPPES — National Plan and Provider Enumeration System

The foundational registry of all US healthcare providers. Contains legal names, credentials, specialties (taxonomy codes), practice addresses, phone numbers, and NPI numbers for over 7 million providers and organizations.

Update cycle: CMS publishes weekly dissemination files. We process new releases quarterly. Source: npiregistry.cms.hhs.gov

Open Payments

Financial transfers from pharmaceutical and medical device companies to physicians and teaching hospitals, reported under the Physician Payments Sunshine Act. Covers general payments, research payments, and ownership interests.

Update cycle: Annual. CMS publishes the prior calendar year's data in the second quarter of the following year (e.g., 2023 data published mid-2024). Source: openpaymentsdata.cms.gov

Medicare Provider Utilization and Payment Data (Part B)

Procedure-level billing data for all Medicare Part B services. Shows procedure codes, service counts, Medicare allowed amounts, and Medicare payments for each provider-procedure combination with 11 or more claims.

Update cycle: Annual, with approximately a two-year publication lag. CMS typically releases data in April for the year two years prior. Source: data.cms.gov

PECOS — Provider Enrollment & Certification System

Tracks provider enrollment status in Medicare and Medicaid. We use publicly available PECOS data to verify whether a provider is currently enrolled in Medicare.

Update cycle: Published periodically by CMS. Source: data.cms.gov

Data Disclaimer — Data sourced from the Centers for Medicare & Medicaid Services (CMS): National Plan and Provider Enumeration System (NPPES), Open Payments program, Medicare Provider Utilization and Payment Data, and Provider Enrollment & Certification data (PECOS). Published under the Freedom of Information Act (FOIA). This website is not affiliated with, endorsed by, or authorized by CMS, HHS, or the U.S. Government. Data may contain errors as reported to CMS by providers and reporting entities. Industry payment disclosure alone establishes neither wrongdoing nor legality. Medicare data reflects only patients aged 65+ or those with qualifying disabilities. For corrections, contact CMS directly. This information does not constitute medical advice and should not be used as the sole basis for choosing a healthcare provider. Procedure descriptions use plain language and do not reference CPT® codes, which are copyrighted by the American Medical Association. Full methodology → · Report a data error → · Privacy policy →