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E11.9 ICD-10-CM Code: Type 2 diabetes mellitus without complications

Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.

Coding at a Glance

Tabular directives
3 inclusion terms · 9 Excludes1 · 5 use-additional codes
Risk adjustment
CMS-HCC V28: 1 category · CMS-HCC V22 category 19 · RxHCC V08 category 31

Inpatient Payment Groups (MS-DRG)

Potential MS-DRG participation — not a DRG assignment.

MS-DRGs this diagnosis helps define, as principal or secondary, per the CMS ICD-10-CM/PCS MS-DRG Definitions Manual v43, Appendix B.

A diagnosis appearing in a group's logic does not by itself determine the DRG assigned to a stay; the grouper uses the full claim.

Risk Adjustment (CMS-HCC)

Payment categories this diagnosis maps to under CMS-HCC V28, payment year 2026.

  • HCC 38 — Diabetes with Glycemic, Unspecified, or No Complications

Other models: CMS-HCC V22 HCC 19 · RxHCC V08 HCC 31

Risk scores depend on the enrollee's full accepted diagnosis set and segment; a category mapping alone does not determine payment.

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for E11.9 in the official ICD-10-CM tabular list, quoted as published.

Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2026Effective: October 1, 2025

Notes without a marker are published on E11.9 itself; “inherited from” names the category or block whose note applies here.

Includes

Conditions the official ICD-10-CM tabular list includes under this code.

  • diabetes (mellitus) due to insulin secretory defect
  • diabetes NOS
  • insulin resistant diabetes (mellitus)

Source: inherited from E11

Excludes1 — Not Coded Here

Conditions generally not reported together with this code (Excludes1) -- an error unless the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).

Use Additional Code

Supplementary codes the tabular list directs you to add.

  • Use additional code to identify control using:
  • injectable non-insulin antidiabetic drugs (Z79.85)
  • insulin (Z79.4)
  • oral antidiabetic drugs (Z79.84)
  • oral hypoglycemic drugs (Z79.84)

Source: inherited from E11

Coder workflow for E11.9

MedCoder structured workflow — derived from this code’s own official record

Before you code E11.9

  1. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with E11.9. Excludes1 conditions are not reported together with this code unless the record shows they are unrelated (Guidelines I.A.12.a).

    See the official tabular notes

Choose the right path

  1. Does the documentation support a condition named in E11.9’s Excludes1 note?
    Yes → Do not simply proceed: review the excluded code. Both are reported only when the record shows the two conditions are unrelated.
    No → Continue.

    ReviewE11.A, E08, E09, O24.4, P70.2, E13

Consider E11.9. Then work the Use Additional Code note, and confirm the code is valid for the date of service in the Verify section.

Documentation check

The provider’s diagnostic statement
Codes are assigned from the provider’s documented diagnosis, not from clinical criteria, test values or a medication list (Guidelines I.A.19).
The associated condition or complication
Whether the associated condition the title names is documented; the “with” convention presumes some links, and a provider statement that the conditions are unrelated defeats it (Guidelines I.A.15).
The conditions the Use Additional Code note names
Reported with this code when documented; a conditional instruction (“if applicable”, “if known”) applies only when the record supports it.
Diabetes type or cause, each complication, and medication use
The type is documented, not inferred from medication (Guidelines I.C.4.a.3); each documented complication takes its own combination code.

Official instructions as workflow

  • Excludes1 — check before selecting E11.9(9 notes)

    Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with E11.9: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

    CompareE11.A, E08, E09, O24.4, P70.2, E13

    See the official tabular notes · Guidelines I.A.12.a

  • Use Additional Code — after identifying E11.9(5 notes)

    Coding workflow: Check whether the documentation supports the additional code(s) the note names, and report them with E11.9 when it does. Where the instruction is conditional (“if applicable”, “if known”), it applies only when the record documents the condition.

    ReviewZ79.85, Z79.4, Z79.84

    See the official tabular notes · Guidelines I.A.13

Every row is derived from this code’s own record — its title, tabular notes, 7th-character family and same-category siblings — with fixed MedCoder wording; nothing is inferred about a patient. The official notes and guideline text are in the sections each row links to, and they control.

Before you code E11.9

MedCoder editorial — not official ICD-10-CM text; reviewed against the cited source

This checklist routes you to the categories to review — it does not determine the final code.

E11.9 asserts three things at once: the diabetes is type 2, no complication is documented, and the disease is not in remission. The diabetes codes are combination codes — a documented complication or a different type or cause moves the case off E11.9 entirely. Check for these before settling on it.

  • Any diabetic complication documented — kidney, eye, nerve, circulatory, skin, or other → the specific E11.- combination rows

    The diabetes codes combine type, body system, and complication in one code; assign as many E11.- combination codes as needed for all documented complications (Guidelines I.C.4.a). E11.9 states that none exist.

  • Type 1 diabetes documented → E10.- Type 1 diabetes mellitus

    E11’s Excludes1 routes type 1 to E10.- — and neither age nor insulin use establishes type 1 by itself (I.C.4.a.1, I.C.4.a.3).

  • Diabetes documented as due to another condition → E08.- Diabetes due to underlying condition

    Secondary diabetes is always caused by another condition or event (I.C.4.a.6); E08.- carries a Code First note for the underlying condition.

  • Diabetes documented as drug- or chemical-induced → E09.- Drug or chemical induced diabetes mellitus

    A documented drug or toxin cause leaves E11 by its own Excludes1; E09.- sequences with the responsible substance’s code.

  • Postpancreatectomy, postprocedural, or other secondary diabetes documented → E13.- Other specified diabetes mellitus

    E11’s Excludes1 sends all three to E13.- — surgery-caused diabetes is never coded as ordinary type 2.

  • Diabetes in pregnancy, childbirth, or the puerperium → O24.- Diabetes mellitus in pregnancy

    Chapter 15 takes over: pre-existing diabetes complicating pregnancy is O24.0-O24.3, and gestational diabetes (O24.4-) is an E11 Excludes1 — it is never an E11.- code.

  • Provider documents the type 2 diabetes as in remission → E11.A Type 2 diabetes in remission

    E11.9’s own Excludes1. Remission requires a provider statement — "resolved" is not synonymous with remission, and unclear documentation is a query, not an inference (I.C.4.a.1).

  • Type of diabetes not documented at all → the E11.- default rule

    When the type is not documented the default is E11.- — even when the patient uses insulin (I.C.4.a.2-3); the control agent is captured with a Z79.- code, not a type change.

The diabetes combination rows run on the same "with" convention as the hypertension families — a documented complication is presumed related to the diabetes unless the provider states otherwise. The "With" Convention: When ICD-10-CM Presumes Two Conditions Are Related →

Provider documentation and the ICD-10-CM Official Guidelines control; verify against the official tabular notes on this page.

Code Overview

Type 2 diabetes mellitus without complications is a billable ICD-10-CM diagnosis code (E11.9).

MedCoder summary Summary composed by MedCoder from this code's official ICD-10-CM record. The tabular instructional notes themselves appear verbatim below.

Indexed Clinical Terms (2)

Official source data — entries quoted as published, in the Index’s own lookup phrasing

Clinical term phrases from the official ICD-10-CM Index to Diseases and Injuries that map to this code. These are alphabetic-index entries shown as the Index writes them — lookup phrasing, not necessarily the wording of a final diagnosis.

Official Coding Guidelines

Official source data — quoted verbatim from the CMS/NCHS Official Guidelines

Official source data — quoted verbatim from the CMS/NCHS Official Guidelines

Verbatim excerpts from the ICD-10-CM Official Guidelines for Coding and Reporting (CMS/NCHS) that govern this code.

Chapter 4: Endocrine, Nutritional, and Metabolic Diseases (E00 -E89)

2) Type of diabetes mellitus not documented If the type of diabetes mellitus is not documented in the medical record the default is E11.-, Type 2 diabetes mellitus.

Chapter 4: Endocrine, Nutritional, and Metabolic Diseases (E00 -E89)

3) Diabetes mellitus and the use of insulin, oral hypoglycemics, and injectable non-insulin drugs If the documentation in a medical record does not indicate the type of diabetes but does indicate that the patient uses insulin, code E11-, Type 2 diabetes mellitus, should be assigned. Additional code(s) should be assigned from category Z79 to identify the long-term (current) use of insulin, oral hypoglycemic drugs, or injectable non-insulin antidiabetic, as follows: If the patient is treated with both oral hypoglycemic drugs and insulin, both code Z79.4, Long term (current) use of insulin, and code Z79.84, Long term (current) use of oral hypoglycemic drugs, should be assigned. If the patient is treated with both insulin and an injectable non-insulin antidiabetic drug, assign codes Z79.4, Long term (current) use of insulin, and Z79.85, Long-term (current) use of injectable non-insulin antidiabetic drugs. If the patient is treated with both oral hypoglycemic drugs and an injectable non-insulin antidiabetic drug, assign codes Z79.84, Long term (current) use of oral hypoglycemic drugs, and Z79.85, Long-term (current) use of injectable non-insulin antidiabetic drugs. Code Z79.4 should not be assigned if insulin is given temporarily to bring a type 2 patient’s blood sugar under control during an encounter.

Coding Notes

MedCoder editorial — not official ICD-10-CM text; reviewed against the cited source

What this code means

E11.9 is the resting state of the type 2 family: diabetes documented with no complication, no stated cause, and no remission statement. Everything that moves a record off it is a documentation event — a complication engages the combination rows (which pair the diabetes and the affected body system in one code), a documented cause moves the case to E08/E09/E13, pregnancy moves it to chapter 15, and a provider remission statement moves it to E11.A. What never moves it is the treatment picture alone: insulin use without a documented type still defaults to E11.-.

Coding guidance

  • Report the control agents alongside: category E11 carries a Use Additional Code note for insulin (Z79.4), oral antidiabetic drugs (Z79.84), and injectable non-insulin antidiabetics (Z79.85) — combinations per I.C.4.a.3.
  • Z79.4 is not assigned when insulin is given temporarily to bring blood sugar under control during an encounter (I.C.4.a.3).
  • Complications are additive, not exclusive: assign as many codes from E08-E13 as needed to identify all documented associated conditions, sequenced by the reason for the encounter (I.C.4.a).
  • The complication link runs on the "with" convention — "diabetes with" a listed condition is presumed related unless the provider states the conditions are unrelated (I.A.15).

Decision-rule scenarios

Documentation: Type 2 diabetes and stage 3 CKD both documented, with no sentence connecting them.

Coding question: Does E11.9 stand next to the N18 code?

Rule: No — the "with" convention presumes the link: the kidney combination row (E11.22 territory) applies with the N18.- stage as an additional code, and E11.9 leaves the claim. Only a provider statement that the CKD is unrelated separates them.

Documentation: "Diabetes" documented with no type; the medication list shows insulin.

Coding question: Does insulin use make it type 1?

Rule: No — undocumented type defaults to E11.- (I.C.4.a.2), and insulin use does not change that (I.C.4.a.3); Z79.4 captures the insulin. Type is a provider statement, not an inference from therapy.

Documentation: The provider writes "type 2 diabetes, resolved."

Coding question: Is that E11.A?

Rule: Not on that word alone — the guideline states "resolved" is not synonymous with remission and directs a query when remission status is unclear (I.C.4.a.1). E11.A requires a documented remission statement.

Documentation: Diabetes documented following a partial pancreatectomy.

Coding question: Is this still the E11 family?

Rule: No — postpancreatectomy diabetes is an E11 Excludes1 routed to E13.-; the secondary-diabetes rules (I.C.4.a.6) govern cause and sequencing.

Scenarios state the decision rule, not a code assignment — code selection always follows the provider's documentation and the ICD-10-CM Official Guidelines.

Documentation checklist

  • The documented type — and where none is stated, the E11.- default applies rather than an inferred type.
  • Every documented complication, each of which selects a combination row and may require its own additional code (N18.- stage, ulcer site, etc.).
  • Any documented cause: underlying condition, drug or chemical, pancreatectomy or other procedure.
  • Long-term control agents — insulin, oral agents, injectable non-insulin agents — for the Z79.- companions.
  • Pregnancy status, and any provider remission statement.

Codes are assigned from provider documentation; a coder never infers a diagnosis.

Common mistakes

  • Keeping E11.9 on a claim that also carries a documented diabetic complication — the combination row replaces it; E11.9 means "no complications."
  • Inferring type 1 from insulin use or patient age — type is documentation, and the undocumented default is E11.- (I.C.4.a.2-3).
  • Dropping the Z79.- control-agent code the category’s Use Additional note asks for — or assigning Z79.4 for temporary insulin.
  • Coding "resolved" diabetes as E11.A without a remission statement — the guideline separates the two words explicitly.
  • Coding gestational diabetes with an E11.- code — O24.4- is an E11 Excludes1.

Written and reviewed by MedCoder against the official ICD-10-CM files; educational, not medical or billing advice. The official tabular notes and guidelines above take precedence in every case.

Verify Before Coding

  • Questionable admission. The Medicare Code Editor lists this among its questionable-admission codes: reported as the principal diagnosis, it is not usually sufficient justification for an inpatient admission on its own, so it flags the admission as questionable. The code itself remains acceptable as principal.

From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim in Claim Check.

Relationships & Classification

MedCoder structured relationships — computed from published CMS and AHRQ datasets

Other codes that name E11.9 or its code family, from the CMS ICD-10-CM tabular instructional notes. Tabular-note edges are stored at the code family level that carries each note.

Referenced by 22 Excludes1 notes across 8 chapters: E08 — Diabetes mellitus due to underlying condition (via E11.-), E09 — Drug or chemical induced diabetes mellitus (via E11.-), E10 — Type 1 diabetes mellitus (via E11.-), E11.A — Type 2 diabetes mellitus without complications in remission, E74 — Other disorders of carbohydrate metabolism (via E11.-), G54.5 — Neuralgic amyotrophy (via E11.-), G59 — Mononeuropathy in diseases classified elsewhere (via E11.-), G63 — Polyneuropathy in diseases classified elsewhere (via E11.-), G99.0 — Autonomic neuropathy in diseases classified elsewhere (via E11.-), H20.0 — Acute and subacute iridocyclitis (via E11.-), I73.8 — Other specified peripheral vascular diseases (via E11.-), I79.8 — Other disorders of arteries, arterioles and capillaries in diseases classified elsewhere (via E11.-), L92.1 — Necrobiosis lipoidica, not elsewhere classified (via E11.-), L99 — Other disorders of skin and subcutaneous tissue in diseases classified elsewhere (via E11.-), M14 — Arthropathies in other diseases classified elsewhere (via E11.-), M14.6 — Charcôt's joint (via E11.-), M90 — Osteopathies in diseases classified elsewhere (via E11.-), N08 — Glomerular disorders in diseases classified elsewhere (via E11.-), N16 — Renal tubulo-interstitial disorders in diseases classified elsewhere (via E11.-), N76.82 — Fournier disease of vagina and vulva (via E11.-), +2 more.

These codes’ tabular lists mark this diagnosis as mutually exclusive — not reported together unless the conditions are documented as unrelated.

Referenced by 2 Excludes2 notes across 2 chapters: H35 — Other retinal disorders (via E11.-), I96 — Gangrene, not elsewhere classified (via E11.-).

These codes’ tabular lists name this diagnosis as distinct — both may be reported when both are documented.

Referenced by 1 Code First instruction: D84.81 — Immunodeficiency due to conditions classified elsewhere (via E11.-).

Each of these codes carries a Code First note naming this condition — when that code is reported, THIS code is sequenced first, ahead of it.

Referenced by 1 Code Also instruction: N76.82 — Fournier disease of vagina and vulva (via E11.-).

These codes suggest coding this condition alongside when both are present.

MS-DRG Grouper Relationships (FY2026)

Potential MS-DRG participation — not a DRG assignment.

FY2026 MS-DRG: not on the CMS CC/MCC list — as a secondary diagnosis this code does not change MS-DRG severity for that release.

Named in the grouper logic of 3 MS-DRGs: DRG 637 (MDC 10), DRG 638 (MDC 10), DRG 639 (MDC 10).

From the CMS MS-DRG Definitions Manual (Appendices B and C). Actual DRG assignment depends on the complete claim.

Clinical classification (AHRQ CCSR):END002 — Diabetes mellitus without complication (default); END005 — Diabetes mellitus, Type 2.

Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses. Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality.

Related Codes

Same CMS-HCC risk category (V28)

CMS maps these diagnoses to the same Hierarchical Condition Category (Diabetes with Glycemic, Unspecified, or No Complications) for risk-adjusted payment.

E08.649 — Diabetes mellitus due to underlying condition with hypoglycemia without coma, E08.65 — Diabetes mellitus due to underlying condition with hyperglycemia, E08.8 — Diabetes mellitus due to underlying condition with unspecified complications, E08.9 — Diabetes mellitus due to underlying condition without complications, E10.649 — Type 1 diabetes mellitus with hypoglycemia without coma, E10.65 — Type 1 diabetes mellitus with hyperglycemia, E10.8 — Type 1 diabetes mellitus with unspecified complications, E10.9 — Type 1 diabetes mellitus without complications, E11.649 — Type 2 diabetes mellitus with hypoglycemia without coma, E11.65 — Type 2 diabetes mellitus with hyperglycemia, E11.8 — Type 2 diabetes mellitus with unspecified complications, E13.649 — Other specified diabetes mellitus with hypoglycemia without coma, E13.65 — Other specified diabetes mellitus with hyperglycemia, E13.8 — Other specified diabetes mellitus with unspecified complications, E13.9 — Other specified diabetes mellitus without complications, Z79.4 — Long term (current) use of insulin

Related risk categories

These categories interact through CMS's HCC hierarchy — one can suppress the other's risk-adjustment weight when both are present on a claim.

Pancreas Transplant Status, Diabetes with Severe Acute Complications, Diabetes with Chronic Complications

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical categories (Diabetes mellitus without complication, Diabetes mellitus, Type 2).

E11.621 — Type 2 diabetes mellitus with foot ulcer, E11.622 — Type 2 diabetes mellitus with other skin ulcer, E11.628 — Type 2 diabetes mellitus with other skin complications, E11.630 — Type 2 diabetes mellitus with periodontal disease, E11.638 — Type 2 diabetes mellitus with other oral complications, E11.641 — Type 2 diabetes mellitus with hypoglycemia with coma, E11.649 — Type 2 diabetes mellitus with hypoglycemia without coma, E11.65 — Type 2 diabetes mellitus with hyperglycemia, E11.69 — Type 2 diabetes mellitus with other specified complication, E11.8 — Type 2 diabetes mellitus with unspecified complications, E11.A — Type 2 diabetes mellitus without complications in remission, E13.9 — Other specified diabetes mellitus without complications, E89.1 — Postprocedural hypoinsulinemia, O24.011 — Pre-existing type 1 diabetes mellitus, in pregnancy, first trimester, O24.012 — Pre-existing type 1 diabetes mellitus, in pregnancy, second trimester, O24.013 — Pre-existing type 1 diabetes mellitus, in pregnancy, third trimester, O24.019 — Pre-existing type 1 diabetes mellitus, in pregnancy, unspecified trimester, O24.02 — Pre-existing type 1 diabetes mellitus, in childbirth, O24.03 — Pre-existing type 1 diabetes mellitus, in the puerperium, O24.111 — Pre-existing type 2 diabetes mellitus, in pregnancy, first trimester, +127 more

Same Index main term, other category

The ICD-10-CM Index to Diseases and Injuries files this code under the main term “Diabetes, diabetic”; these codes share that main term but sit in a different category of the Tabular List.

E10.641 — Type 1 diabetes mellitus with hypoglycemia with coma (type 1, with, hypoglycemia, with coma), E10.649 — Type 1 diabetes mellitus with hypoglycemia without coma (type 1, with, hypoglycemia), E10.65 — Type 1 diabetes mellitus with hyperglycemia (type 1, with, hyperglycemia), E10.69 — Type 1 diabetes mellitus with other specified complication (type 1, with, osteomyelitis), E10.8 — Type 1 diabetes mellitus with unspecified complications (type 1, with, complication), E10.9 — Type 1 diabetes mellitus without complications (type 1), E10.A — Type 1 diabetes mellitus, presymptomatic (type 1, early-stage), E10.A0 — Type 1 diabetes mellitus, presymptomatic, unspecified (type 1, presymptomatic), E10.A1 — Type 1 diabetes mellitus, presymptomatic, Stage 1 (type 1, presymptomatic, Stage 1), E10.A2 — Type 1 diabetes mellitus, presymptomatic, Stage 2 (type 1, presymptomatic, Stage 2), E13.00 — Other specified diabetes mellitus with hyperosmolarity without nonketotic hyperglycemic-hyperosmolar coma (NKHHC) (specified type NEC, with, hyperosmolarity), E13.01 — Other specified diabetes mellitus with hyperosmolarity with coma (specified type NEC, with, hyperosmolarity, with coma), E13.10 — Other specified diabetes mellitus with ketoacidosis without coma (specified type NEC, with, ketoacidosis), E13.11 — Other specified diabetes mellitus with ketoacidosis with coma (specified type NEC, with, ketoacidosis, with coma), E13.21 — Other specified diabetes mellitus with diabetic nephropathy (specified type NEC, with, nephropathy), E13.22 — Other specified diabetes mellitus with diabetic chronic kidney disease (specified type NEC, with, chronic kidney disease), E13.29 — Other specified diabetes mellitus with other diabetic kidney complication (specified type NEC, with, renal complication NEC), E13.311 — Other specified diabetes mellitus with unspecified diabetic retinopathy with macular edema (specified type NEC, with, retinopathy, with macular edema), E13.319 — Other specified diabetes mellitus with unspecified diabetic retinopathy without macular edema (specified type NEC, with, retinopathy), E13.321 — Other specified diabetes mellitus with mild nonproliferative diabetic retinopathy with macular edema (specified type NEC, with, retinopathy, nonproliferative, with macular edema), +190 more

Lab tests where this diagnosis supports Medicare coverage (NCD)

Medicare's National Coverage Determination (NCD) program lists this diagnosis as medical justification for these lab tests.

HbA1c Test (Glycated Hemoglobin), Blood Glucose Test, Gamma-glutamyl Transferase (GGT) Test, Iron Panel, Lipid Panel, Thyroid Stimulating Hormone (TSH)

Contextual Map

Every relationship of E11.9 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.

Run E11.9 with these 12 related codes in Claim Check

Hierarchy

Excludes1

Referenced by Excludes1 notes (22)

Referenced by Excludes2 notes

  • H35 — Other retinal disorders[Excludes2](via E11.-): “diabetic retinal disorders (E08.311-E08.359, E09.311-E09.359, E10.311-E10.359, E11.311-E11.359, E13.311-E13.359)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
  • I96 — Gangrene, not elsewhere classified[Excludes2](via E11.-): “gangrene in diabetes mellitus (E08-E13 with .52)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Referenced by Code First instructions

Referenced by Code Also instructions

Clinical classification (CCSR)

Risk adjustment (CMS-HCC)

  • HCC 38 — Diabetes with Glycemic, Unspecified, or No Complications [CMS-HCC]— CMS-HCC V28 · 2026

MS-DRG Grouper

MDC crossing

  • MDC 10 — Endocrine, Nutritional and Metabolic Diseases and Disorders[MDC crossing]: “Endocrine, Nutritional and Metabolic Diseases and Disorders — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs. 5,008 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2026

Index entries

  • Diabetes, diabetic (mellitus) (sugar)[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Diabetes, diabetic (mellitus) (sugar), type 2[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026

Nearest codes (40)

Change history

  • FY2016 — In the code set at ICD-10-CM adoption [Change history]— CMS release files (code change ledger) · icd10cm-fy2016

Real-World Coding Questions

Questions working coders have asked about this code, answered from official sources and reviewed by an editor.

Common coding questions

When is E11.9 the default code?

In two documented-silence cases the Guidelines settle directly: when the type of diabetes is not documented, the default is E11.-; and when the type is not documented but insulin use is, E11.- is still assigned (insulin does not imply type 1), with a Z79.- code for the control agent. Complications change the code, not the type logic — the combination codes are the same “with” convention the hypertension families use; see the ICD-10 “with” convention.

Can E11.9 be a principal diagnosis?

Yes — no MCE edit blocks it, and uncomplicated type 2 diabetes is routinely the reason for an encounter. This is the mirror image of E08.9, which looks like a sibling but is a manifestation code barred from first position with its underlying condition sequenced ahead of it.

What companion code is most often missed with E11.9?

The control-agent Z code: category E11 carries a Use Additional Code note for insulin (Z79.4), oral antidiabetic drugs (Z79.84), and injectable non-insulin antidiabetics (Z79.85). E11.9 itself maps to V28 HCC 38 (Diabetes with Glycemic, Unspecified, or No Complications); documented complications move the claim into HCC 37 or 36 via the specific combination codes.

Sources for this page

Codes, titles, notes, index terms and mappings on this page are transcribed from the datasets below. Relationships MedCoder computed and text MedCoder wrote are labelled where they appear.

Code, title, tabular notes and index terms Official source data
CMS/CDC ICD-10-CM FY2026 tabular list, index and tables, effective October 1, 2025 Release, file and checksum · Publisher’s page
Coding guidelines Official source data
ICD-10-CM Official Guidelines for Coding and Reporting (FY2026), quoted by section Release, file and checksum · Publisher’s page
Claim edits Official source data
CMS Definitions of Medicare Code Edits — v43.1 (April 2026) Release, file and checksum · Publisher’s page
Inpatient payment groups Official source data
CMS MS-DRG Definitions Manual (incl. Appendix B diagnosis index, Appendix C CC/MCC list, Appendix E procedure index) and IPPS Final Rule tables — v43 Release, file and checksum · Publisher’s page
Risk adjustment Official source data
2026 Mid-Year Final ICD-10 Mappings + Model Software (cms.gov/files/zip/2026-midyear-final-icd-10-mappings.zip, 2026-midyear-final-model-software.zip) — CMS-HCC V28, PY2026 mid-year final release Release, file and checksum · Publisher’s page
Change history and date-of-service validity Official source data
CMS ICD-10-CM release addenda, ingested release by release into the change ledger Release, file and checksum · Publisher’s page
Comparisons, relationships and the contextual map MedCoder structured relationship
Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears
Summary, coding notes, decision checklist and FAQ answers MedCoder explanation
Written by MedCoder to explain the sources above: drafted with AI assistance, checked by a person against the release files, and labelled as MedCoder text where it appears. Not official text.

Labels on this page: Official source data · MedCoder structured relationship · MedCoder explanation. How to read the labels · All data sources and release dates

Cite this page

Reference this page in a research guide, syllabus or article. The release is included because code content changes each year.

MedCoder.ai. "E11.9 — Type 2 diabetes mellitus without complications." ICD-10-CM FY2026. https://medcoder.ai/icd10/code/e11.9-type-2-diabetes-mellitus-without-complications

Change history

  • FY2016 — October 1, 2015
    In the code set at ICD-10-CM adoption
    Type 2 diabetes mellitus without complications

No changes since FY2016 — additions, deletions, description changes and billable-status changes are tracked through FY2027 (effective October 1, 2026), and none are recorded for this code. Note changes are tracked from FY2027 only.

Nearest Codes in This Family

Official ICD-10-CM classifications closest to E11.9 in its code family, with their registry titles.

View all codes in the E11 family