E11
Non-Billable (Header)Type 2 diabetes mellitus
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
What This Code Means
E11 is the ICD-10-CM diagnosis code for type 2 diabetes mellitus. E11 sits in the ICD-10-CM chapter for endocrine, nutritional and metabolic diseases (e00-e89), within the section covering diabetes mellitus (e08-e13).
Header codes like E11 cannot be reported on claims directly — they organize child codes that share clinical context but the actual diagnosis must be coded to the highest level of specificity supported by the documentation. Coders should look at E11's child codes and select the one that matches the patient's documented presentation, since payers reject header codes submitted as the primary diagnosis. For risk adjustment workflows, header codes never contribute to a Medicare Advantage member's RAF score on their own; only billable child codes that happen to map to a payment HCC affect risk-adjusted plan payments.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for E11 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Includes
- diabetes (mellitus) due to insulin secretory defect
- diabetes NOS
- insulin resistant diabetes (mellitus)
Excludes 1 — Do NOT code together
- diabetes mellitus due to underlying condition (E08.-)
- drug or chemical induced diabetes mellitus (E09.-)
- gestational diabetes (O24.4-)
- neonatal diabetes mellitus (P70.2)
- postpancreatectomy diabetes mellitus (E13.-)
- postprocedural diabetes mellitus (E13.-)
- secondary diabetes mellitus NEC (E13.-)
- type 1 diabetes mellitus (E10.-)