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 643 through 645. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Thyroid disorders.

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

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.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Capsulitis(joint)
      • thyroid
    • Thyroiditis

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

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 643, 644, 645, with relative weights from 0.7683 to 1.6461 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.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.