2026 ICD-10-CM Diagnosis Code E06.3Autoimmune thyroiditis
ICD-10-CM Codes›E00–E89›E00-E07›E06
- Billable — Valid for Submission
- Chronic Condition
E06.3 is a billable ICD-10-CM diagnosis code for autoimmune thyroiditis. 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.
E06.3 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
Code Classification
Medicare Risk Adjustment (HCC)Billing
E06.3 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.
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.
- Atrophic Hashimoto thyroiditis
- Atrophy of thyroid - acquired
- Autoimmune hypothyroidism
- Autoimmune thyroiditis
- Chronic thyroiditis
- Dementia due to autoimmune encephalitis
- Dementia due to Hashimoto encephalopathy
- Fibrous autoimmune thyroiditis
- Goiter due to thyroiditis
- Goitrous Hashimoto thyroiditis
- Hashimoto thyroiditis
- Hashitoxicosis - transient
- Hyperthyroidism with Hashimoto disease
- Hypothyroidism due to Hashimoto's thyroiditis
- Immunoglobulin G4 related disease
- Immunoglobulin G4 related thyroid disease
- Primary hypothyroidism
- Restrictive ophthalmopathy
- Steroid-responsive encephalopathy associated with autoimmune thyroiditis
- Subacute autoimmune thyroiditis
- Subacute thyroiditis
- Thyroid atrophy
- Thyroid degeneration
- Thyroid eye disease
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Inclusion Terms
- Hashimoto's thyroiditis
- Hashitoxicosis (transient)
- Lymphadenoid goiter
- Lymphocytic thyroiditis
- Struma lymphomatosa
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
thyroiditis E06.3
Disease, diseased See Also: Syndrome;
Lymphadenoid goiter E06.3
Struma See Also: Goiter;
Hashimoto E06.3
lymphomatosa E06.3
autoimmune E06.3
chronic (nonspecific) (sclerosing) E06.5
lymphadenoid E06.3
lymphocytic E06.3
lymphoid E06.3
lymphocytic (chronic) E06.3
lymphoid E06.3
lymphomatous E06.3
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Iatrogenic Primary Hypothyroidism
primary hypothyroidism due to medical or surgical treatment.Primary Hypothyroidism
abnormally low levels of thyroid hormones due to a disorder originating within the thyroid gland.Transient Primary Hypothyroidism
primary hypothyroidism that resolves spontaneously.
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 E06.3 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About E06.3Overview
What is the ICD-10 code for autoimmune thyroiditis?
The ICD-10-CM code for autoimmune thyroiditis is E06.3 (sometimes written as E063). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
Is E06.3 (Thyroiditis) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report autoimmune thyroiditis on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does E06.3 group to?
When autoimmune thyroiditis 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 E06.3?
Under the General Equivalence Mappings, autoimmune thyroiditis converts to ICD-9-CM 245.2 (chr lymphocyt thyroidit). The mapping is a direct match.
Does E06.3 risk-adjust for Medicare Advantage payment?
Not for Medicare Advantage: E06.3 maps to no category in the CMS-HCC V28 model. It still risk-adjusts in the RxHCC Part D (V08) category 44 (Thyroid Disorders).
