Diabetes HCC Coding 2026: V28 E11 Map and MEAT

Quick Answer

E11.9 is a billable ICD-10-CM code. Under CMS-HCC V28 for payment year 2026 it maps to HCC 38. E11.22 maps to HCC 37. E11.00 and E11.10 map to HCC 36. Those three diabetes payment categories all carry the same Community Non-Dual Aged coefficient, 0.166. E11.65 stays on HCC 38. E11.A and E09.9 are verified valid-no-mapping results.

The diabetes HCC line does not get heavier when you move from E11.9 to E11.22. The extra payment HCCs, when they exist, come from a dual map on the same diabetes code or from the additional code the Tabular asks for. Do not assign E11.22 from a problem-list CKD row, and do not use Z79.4 as a stand-in for the diabetes diagnosis.

*Release: FY2026 ICD-10-CM period 2, April 1, 2026 through September 30, 2026. CMS-HCC V28, payment year 2026, is at full weight for non-PACE organizations. Community Non-Dual Aged (CNA) coefficients are shown only where the current CMS source files support them. Interaction terms are applied only inside the RAF tool, so this article does not publish a standalone interaction coefficient.*

At a glance

Checked E11, E09, and related codes. FY2026 period 2 identity plus CMS-HCC V28 mapping:

E11 exists in the FY2026 order file as a non-billable heading. Code to a billable child.

HCC 36 is labeled "Diabetes with Severe Acute Complications." HCC 37 is "Diabetes with Chronic Complications." HCC 38 is "Diabetes with No, Glycemic, or Unspecified Complications." Those labels and the 0.166 CNA values come from the CMS V28 PY2026 relative-factor file. Other enrollment segments use different coefficients in that same file. Do not treat 0.166 as a universal RAF.

For the dual-map rows, the 0.166 figure is the diabetes HCC 37 CNA from the MCP receipt. The second coefficient is the CNA value for that second HCC in the same official factor file.

HCC 36, 37, and 38 carry the same CNA

The V28 payment map follows the ICD-10-CM code, not the word "diabetes."

Checked acute codes (E11.00, E11.10, E11.641) map to HCC 36. Checked chronic-complication codes (E11.21, E11.22, E11.42, E11.51, E11.319, E11.69) map to HCC 37. Checked no-complication, glycemic, and unspecified-complication codes (E11.9, E11.8, E11.65, E11.649) map to HCC 38.

The official V28 hierarchy file places HCC 36 above HCC 37 and HCC 38, and HCC 37 above HCC 38. If a chart supports both a chronic-complication code and E11.9, HCC 38 does not also pay. That is a hierarchy fact from the registered CMS file, not a sequencing preference.

Because HCC 36, 37, and 38 all carry 0.166 CNA, applying that hierarchy does not change the diabetes-line coefficient. Code the complication the record supports because the code has to be correct and because some diabetes codes carry a second payment HCC. Do not recode E11.9 to E11.22 to "pick up" a heavier diabetes weight. That heavier diabetes weight is not in the PY2026 CNA column.

HCC 35, Pancreas Transplant Status, sits above all three diabetes HCCs in the same hierarchy file. This article does not inventory transplant codes.

Glycemic is HCC 38, not HCC 37

E11.65 (hyperglycemia) and E11.649 (hypoglycemia without coma) map to HCC 38. E11.641 (hypoglycemia with coma) maps to HCC 36.

That split is the official V28 assignment, confirmed by MCP mapping receipts. A hyperglycemia code is not a chronic-complication upgrade. If the note supports neuropathy, retinopathy, nephropathy, or another chronic complication, code that complication. Do not treat "uncontrolled" as a synonym for E11.65 unless the record actually supports hyperglycemia.

E11.8, unspecified complications, also maps to HCC 38. Unspecified is allowed when the record cannot support a more specific complication code. Official Guidelines Section I.A.9.b and Section I.B.18 keep that door open. It is still HCC 38, not HCC 37.

Some chronic codes dual-map

Most checked chronic-complication codes map only to HCC 37. Three checked exceptions do not:

Those second HCCs sit in different official hierarchy groups from the diabetes group. HCC 37 does not replace 383, 263, or 298. HCC 263 supersedes HCC 264, HCC 383, and HCC 409. This article does not inventory the L97 sixth-character maps that can move a skin-ulcer row. Look up the site-and-severity code you actually assign. The ulcer last-character desk card owns that table.

The Tabular Use Additional note on E11.621 asks for L97.4- or L97.5- to identify the site of the ulcer. The note on E11.622 asks for L97.1-L97.9 or L98.41-L98.49. Assigning E11.621 without the site code is incomplete ICD-10-CM coding. It is not a way to drop HCC 37.

E11.22 still needs the CKD stage code

E11.22 is the combination code for type 2 diabetes with diabetic chronic kidney disease. It maps to HCC 37. The Tabular Use Additional note says to identify the stage of chronic kidney disease with N18.1-N18.6.

A checked stage-4 code, N18.4, maps to HCC 327. The CNA coefficient in the MCP receipt is 0.514. N18.9, CKD unspecified, is billable and verified no-HCC-mapping. This article does not inventory the rest of the N18 tree. Look up the stage code in the encounter. See the CKD HCC coding guide.

Official Guidelines Section I.A.15 say the word "with" or "in" means "associated with" or "due to" when it appears in a code title, the Alphabetic Index, or a Tabular instructional note. The classification presumes that link unless the documentation clearly states the conditions are unrelated, or another guideline requires an explicit documented linkage. That is why diabetic CKD, diabetic neuropathy, and diabetic retinopathy are coded as related when the Index or Tabular links them with "with." If the note says the CKD is from hypertension only, or the neuropathy is chemotherapy-related, do not force the diabetes combination.

Type is not the HCC. E09.9 is the exception.

E10.9 maps to HCC 38. E10.22 maps to HCC 37. E13.9 and E08.9 map to HCC 38. For those checked codes, the complication character, not the E08/E10/E11/E13 family, selects the diabetes HCC.

E09.9 does not follow that pattern. It is billable, and the V28 map is verified no-HCC-mapping. The official 2026 Final ICD-10-CM Mappings file leaves the V28 column empty for the E09 rows. Do not copy an E11 HCC onto an E09 code.

Official Guidelines Section I.C.4.a.2 say that if the type of diabetes is not documented, the default is E11.-. Section I.C.4.a.3 add that if the record does not state the type but does state that the patient uses insulin, assign E11.- and an additional code from Z79. Age alone does not pick type 1.

E11 Excludes1 names E08.-, E09.-, E10.-, E13.-, gestational diabetes (O24.4-), and neonatal diabetes (P70.2). Official Guidelines Section I.A.12.a define Excludes1 as "NOT CODED HERE!" unless the two conditions are unrelated.

E11.A is not a quieter E11.9

E11.A is billable. It is type 2 diabetes without complications in remission. The V28 map is verified no-HCC-mapping.

E11.9 has an Excludes1 note for E11.A. E11.A has Excludes1 notes for E11.0-E11.8 and for E11.9. Official Guidelines Section I.C.4.a.1(b) assign E11.A only when the provider documents remission. The term "resolved" is not synonymous with remission. Query if that point is unclear.

Remission is not unspecified. Unspecified without complications is E11.9, and E11.9 still maps to HCC 38.

Z79.4 maps to HCC 38. It does not replace the diabetes code.

Z79.4 is billable and maps to HCC 38. Z79.84 and Z79.85 are billable and verified no-HCC-mapping.

The E11 Tabular Use Additional note tells you to identify control with Z79.4, Z79.84, or Z79.85. Official Guidelines Section I.C.4.a.3 say to assign those Z79 codes as additional codes. If the patient is on both insulin and an oral hypoglycemic, assign both Z79.4 and Z79.84. Do not assign Z79.4 when insulin is given only temporarily to bring a type 2 patient's blood sugar under control during the encounter.

Z79.4 can contribute HCC 38 when the diabetes code is missing. That is not a reason to skip the diabetes diagnosis. Code the diabetes. Use Z79.4 as the long-term insulin additional code the Tabular asked for.

What else does not map

Checked verified no-HCC-mapping results that often sit next to a diabetes chart:

The word "diabetes" in the description is not a V28 payment HCC. Look the code up.

Historical V24 reference

The current CMS 2026 Final ICD-10-CM Mappings file contains the generic CMS-HCC V28 column. It does not contain a generic CMS-HCC V24 column. HCC Buddy uses the CMS 2025 Midyear/Final ICD-10-CM Mappings file for its historical CMS-HCC V24, payment year 2025 reference. It does not infer a V24 mapping for FY2026 codes that are absent from that historical file.

The V28 map above applies to CY2026 non-PACE payment. Use the official mapping and model for the payment year and program under review. PACE uses a CY2026 blend and cannot be represented by one V28 or V24 mapping and coefficient.

This article does not publish a V24 coefficient in this section, and it does not turn a missing historical row into "no HCC."

Documentation and the query trigger

Official Guidelines Section I.B.2 require diagnosis codes at the highest number of characters available and at the highest specificity documented in the record. The provider, not the coder, establishes the diagnosis. A joint effort between provider and coder is required to get the documentation complete enough to code (guidelines introduction and Section I.B.18).

What that means on a diabetes chart:

Query when the record is internally inconsistent or incomplete, not to harvest a coefficient. HCC Buddy educational query language, not a CMS form:

"The assessment lists type 2 diabetes with current treatment. Please document whether any diabetic complication is being monitored or treated this visit (including CKD stage, neuropathy, retinopathy, or ulcer), and whether the diabetes is in remission."

If the provider cannot specify a complication, keep E11.9 or E11.8 as the record supports. That is the guideline-compliant answer. Both still map to HCC 38. See provider query templates.

Primary sources

Disclaimer

HCC Buddy is not affiliated with, endorsed by, or approved by CMS, CDC, NCHS, AHA, AHIMA, or WHO. This page is original HCC Buddy education for risk-adjustment coders. It does not replace the official classification, the Official Guidelines, payer policy, or coder judgment. Every mapping and coefficient above is scoped to FY2026 period 2 and CMS-HCC V28 payment year 2026 CNA unless a different source is named. Re-check the official file for the date of service in front of you. HCC Buddy does not store PHI.

Written by the HCC Buddy Coding Team.

Frequently Asked Questions

Does E11.9 still map to an HCC under V28?

Yes. E11.9 is billable, and the FY2026 period 2 MCP receipt plus the official 2026 Final ICD-10-CM Mappings file both assign CMS-HCC V28 category 38. The CNA coefficient in the PY2026 V28 factor file is 0.166. E11.A, type 2 diabetes in remission, is the verified no-HCC-mapping neighbor, not E11.9.

If I code E11.22 instead of E11.9, does the diabetes RAF go up?

No. E11.22 maps to HCC 37 and E11.9 maps to HCC 38. Both carry 0.166 CNA. HCC 37 supersedes HCC 38, so you do not stack them. The reason to code E11.22 when the record supports diabetic CKD is that the code is correct, the combination is audit-defensible, and the Tabular still wants an N18.1-N18.6 stage code. A checked N18.4 maps to a separate CKD HCC.

Does E11.65 map to HCC 37?

No. E11.65 maps to HCC 38, the same glycemic-and-unspecified category as E11.9 and E11.8. E11.649 also maps to HCC 38. Hypoglycemia with coma (E11.641) maps to HCC 36.

Can Z79.4 replace the diabetes diagnosis?

No. Z79.4 maps to HCC 38, and the E11 Tabular Use Additional note names it. Official Guidelines Section I.C.4.a.3 treat it as an additional long-term insulin code. Code the diabetes. Then add Z79.4 when long-term insulin use is documented and the temporary-insulin exception does not apply.

Does E09.9 map like E11.9?

No. E09.9 is billable and verified no-HCC-mapping under V28. The official Final mapping file leaves that V28 column empty. Look up the specific E09 code. Do not copy an E11 HCC onto it.