2026 ICD-10-CM Diagnosis Code E06.9Thyroiditis, unspecified

ICD-10-CM Codes›E00–E89›E00-E07›E06

ICD-10-CM E06.9
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

E06.9 is a billable ICD-10-CM diagnosis code for thyroiditis, unspecified. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 11 through 13, 643 through 645. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Thyroid disorders.

E06.9 does not risk-adjust for Medicare Advantage under the CMS-HCC V28 model. It still risk-adjusts in the RxHCC Part D (V08) category 44 for payment year 2026.

Code Identity

ICD-10-CM Code
E06.9
Billable Status
Yes — Valid for Submission
Code Describes
Thyroiditis, unspecified
Short Description
Thyroiditis, unspecified
Same as the full description in the CMS dataset.
Parent Code
E06
Thyroiditis

Code Classification

ChapterE00–E89Endocrine, nutritional and metabolic diseases
SectionE00-E07Disorders of thyroid gland
CategoryE06Thyroiditis
This CodeE06.9Thyroiditis, unspecified

Medicare Risk Adjustment (HCC)Billing

E06.9 does not risk-adjust for Medicare Advantage under the CMS-HCC V28 model, but it maps to payment categories in the other CMS models shown below.

CMS-HCC V28 (Medicare Advantage Payment Model)
Not mapped
no payment category in the model that pays 100% of MA risk scores
Prior Model (CMS-HCC V24)
Not mapped under V24
this diagnosis newly risk-adjusts under the V28 model
Part D (RxHCC)
RxHCC 44 — Thyroid Disorders
also risk-adjusts in the Part D prescription drug model (V08)

Source: CMS Payment Year 2026 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Euthyroid thyroiditis
  • Focal thyroiditis
  • Goiter due to thyroiditis
  • Hypothyroidism due to thyroiditis
  • Silent thyroiditis
  • Thyroid disease in mother complicating childbirth
  • Thyroid disease in pregnancy
  • Thyroid infection
  • Thyroiditis
  • Thyroiditis in mother complicating childbirth
  • Thyroiditis in pregnancy

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR END001
Thyroid disorders
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Hashimoto Disease

    chronic autoimmune thyroiditis, characterized by the presence of high serum thyroid autoantibodies; goiter; and hypothyroidism.

  • Postpartum Thyroiditis

    transient autoimmune thyroiditis occurring in the postpartum period. it is characterized by the presence of high titers of autoantibodies against thyroid peroxidase and thyroglobulin. clinical signs include the triphasic thyroid hormone pattern: beginning with thyrotoxicosis, followed with hypothyroidism, then return to euthyroid state by 1 year postpartum.

  • Thyroiditis

    inflammatory diseases of the thyroid gland. thyroiditis can be classified into acute (thyroiditis, suppurative), subacute (granulomatous and lymphocytic), chronic fibrous (riedel's), chronic lymphocytic (hashimoto disease), transient (postpartum thyroiditis), and other autoimmune thyroiditis subtypes.

  • Thyroiditis, Autoimmune

    inflammatory disease of the thyroid gland due to autoimmune responses leading to lymphocytic infiltration of the gland. it is characterized by the presence of circulating thyroid antigen-specific t-cells and thyroid autoantibodies. the clinical signs can range from hypothyroidism to thyrotoxicosis depending on the type of autoimmune thyroiditis.

  • Thyroiditis, Subacute

    spontaneously remitting inflammatory condition of the thyroid gland, characterized by fever; muscle weakness; sore throat; severe thyroid pain; and an enlarged damaged gland containing giant cells. the disease frequently follows a viral infection.

  • Thyroiditis, Suppurative

    acute inflammatory disease of the thyroid gland due to infections by bacteria; fungi; or other microorganisms. symptoms include tender swelling, fever, and often with leukocytosis.

Patient EducationClinical

Thyroid Diseases

Your thyroid is a small, butterfly-shaped gland in the front of your neck. It makes hormones that control the way the body uses energy. These hormones affect nearly every organ in your body and control many of your body's most important functions. For example, they affect your breathing, heart rate, weight, digestion, and moods.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert E06.9 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
245.9 Thyroiditis NOS
Exact Match The mapping is direct, with no qualifiers.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About E06.9Overview

What is the ICD-10 code for thyroiditis, unspecified?

The ICD-10-CM code for thyroiditis, unspecified is E06.9 (sometimes written as E069). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

Is E06.9 (Thyroiditis) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report thyroiditis, unspecified on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does E06.9 group to?

When thyroiditis, unspecified is the principal diagnosis on an inpatient stay, it groups to MS-DRG 11, 12, 13, 643, 644, 645, with relative weights from 0.7683 to 5.4541 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of E06.9?

Under the General Equivalence Mappings, thyroiditis, unspecified converts to ICD-9-CM 245.9 (thyroiditis NOS). The mapping is a direct match.

Does E06.9 risk-adjust for Medicare Advantage payment?

Not for Medicare Advantage: E06.9 maps to no category in the CMS-HCC V28 model. It still risk-adjusts in the RxHCC Part D (V08) category 44 (Thyroid Disorders).