Question 1

Which ICD-10-CM edition is the public default?

Accepted Answer

FY2027 covers dates of service from October 1, 2026 through September 30, 2027. Select a historical edition for an earlier date.

Question 2

Are FY2027 HCC mappings verified?

Accepted Answer

CMS-HCC V28 mappings come from the CMS 2027 Initial ICD-10-CM Mappings, which apply to 2026 dates of service (payment year 2027), and RAF values from the CMS-HCC V28 relative factors. For 2027 dates of service, CMS has not yet published the payment year 2028 mappings. CMS has not yet mapped the new FY2027 codes, and ESRD, RxHCC, PACE and HHS-HCC remain pending for this edition.

Question 3

Where can I check the official instructions?

Accepted Answer

Open the Code Book for the selected edition to read Tabular instructions, the Alphabetic Index and the Official Guidelines.

FY2027 ICD-10-CM reference