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AB2D v3 is here!

Read the full announcement on AB2D v3 or learn how to migrate. Access to v1 and v2 will be removed on July 30, 2027.

Introducing AB2D v3

AB2D v3 delivers faster, more reliable access to Medicare Parts A and B claims data for Part D plan sponsors. Platform-level improvements include timelier data, better support for Part D programs, and improved standardization.

Better support your Part D programs

  • Get fresher, more complete claims data for Medication Therapy Management (MTM), Star Ratings measures, and fraud, waste, and abuse prevention.
  • Use improved provider and prescriber data to help care teams catch drug interactions and lower beneficiary out-of-pocket costs.

Standardize your FHIR-based data systems

  • Map and aggregate data more easily with improved FHIR conformance.
  • Process less duplicate data with automatic claims deduplication.

AB2D v3 improvements

More updates per week

Patient and enrollment data refreshes 6 times per week, up from once per week. Parts A and B claims refresh weekly on Mondays.

Fewer missing and duplicate records

v3 largely removes the delay in new enrollees appearing in AB2D. A patient merge feature points all MBIs for a patient to a single active record.

Easier claims tracking

v3 returns only the most recent version of each claim. A new Claim Control Number (CCN) field lets you track claims across claim updates. The CCN replaces Group Claim ID in earlier API versions.

Targeted exports

The new _typeFilter parameter lets you download only the data you need by filtering by service date.

Improved FHIR extensions and code systems

v3 uses standard FHIR StructureDefinition and CodeSystem resources for extensions and code systems.

What stays the same?

The workflow is the same:

  1. Authenticate
  2. Start a job
  3. Check status
  4. Download files

AB2D v3 still returns ExplanationOfBenefit resources in NDJSON format, and 173 of 252 fields are unchanged.

What this means for your organization

  • Reduced development time: Most fields carry over, with the Data Dictionary mapping every change
  • Improved data quality: A single source removes duplicate patients and claim versions
  • Faster access to claims data: Faster, more frequent updates mean more accurate insights

Ready to get started?

Questions? Contact the AB2D team at AB2D@cms.hhs.gov.

cms.gov

official website of the U.S. Department of Health and Human Services and the Centers for Medicare & Medicaid Services.

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