ICD-10-CM Tabular Index · Chapter 4 · FY 2026 E05

Thyrotoxicosis [hyperthyroidism] (E05) ICD-10-CM

The E05 code range covers thyrotoxicosis [hyperthyroidism] with 22 ICD-10-CM diagnosis codes. 14 of them are billable and valid for claim submission in fiscal year 2026, and the category headers group them but cannot themselves be billed.

✓ Built from the official CMS FY 2026 datasetEffective Oct 1, 2025 – Sep 30, 2026
22
Diagnosis Codes
14
Billable Codes
E05
Code Range
E00–E07
Parent Section

Type 1 Excludes

A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.

ICD-10-CM

Codes in the E05 Range 22 codes · 14 billable

22 of 22 shown
  • E05 Thyrotoxicosis [hyperthyroidism]Non-billable
  • E05.0 Thyrotoxicosis with diffuse goiterNon-billable
  • E05.00 Thyrotoxicosis with diffuse goiter without thyrotoxic crisis or storm
  • E05.01 Thyrotoxicosis with diffuse goiter with thyrotoxic crisis or storm
  • E05.1 Thyrotoxicosis with toxic single thyroid noduleNon-billable
  • E05.10 Thyrotoxicosis with toxic single thyroid nodule without thyrotoxic crisis or storm
  • E05.11 Thyrotoxicosis with toxic single thyroid nodule with thyrotoxic crisis or storm
  • E05.2 Thyrotoxicosis with toxic multinodular goiterNon-billable
  • E05.20 Thyrotoxicosis with toxic multinodular goiter without thyrotoxic crisis or storm
  • E05.21 Thyrotoxicosis with toxic multinodular goiter with thyrotoxic crisis or storm
  • E05.3 Thyrotoxicosis from ectopic thyroid tissueNon-billable
  • E05.30 Thyrotoxicosis from ectopic thyroid tissue without thyrotoxic crisis or storm
  • E05.31 Thyrotoxicosis from ectopic thyroid tissue with thyrotoxic crisis or storm
  • E05.4 Thyrotoxicosis factitiaNon-billable
  • E05.40 Thyrotoxicosis factitia without thyrotoxic crisis or storm
  • E05.41 Thyrotoxicosis factitia with thyrotoxic crisis or storm
  • E05.8 Other thyrotoxicosisNon-billable
  • E05.80 Other thyrotoxicosis without thyrotoxic crisis or storm
  • E05.81 Other thyrotoxicosis with thyrotoxic crisis or storm
  • E05.9 Thyrotoxicosis, unspecifiedNon-billable
  • E05.90 Thyrotoxicosis, unspecified without thyrotoxic crisis or storm
  • E05.91 Thyrotoxicosis, unspecified with thyrotoxic crisis or storm

Clinical Terms in This Code Range

Definitions from the National Library of Medicine for conditions coded in the E05 range.

Graves Disease

A common form of hyperthyroidism with a diffuse hyperplastic GOITER. It is an autoimmune disorder that produces antibodies against the THYROID STIMULATING HORMONE RECEPTOR. These autoantibodies activate the TSH receptor, thereby stimulating the THYROID GLAND and hypersecretion of THYROID HORMONES. These autoantibodies can also affect the eyes (GRAVES OPHTHALMOPATHY) and the skin (Graves dermopathy).

Hyperthyroidism

Hypersecretion of THYROID HORMONES from the THYROID GLAND. Elevated levels of thyroid hormones increase BASAL METABOLIC RATE.

Thyrotoxicosis

A hypermetabolic syndrome caused by excess THYROID HORMONES which may come from endogenous or exogenous sources. The endogenous source of hormone may be thyroid HYPERPLASIA; THYROID NEOPLASMS; or hormone-producing extrathyroidal tissue. Thyrotoxicosis is characterized by NERVOUSNESS; TACHYCARDIA; FATIGUE; WEIGHT LOSS; heat intolerance; and excessive SWEATING.

About the E05 Code Range

The ICD-10 code section E05 is used to classify thyrotoxicosis, also known as hyperthyroidism, which refers to an overactive thyroid gland producing excessive thyroid hormones. These codes help specify the exact type and severity, including whether a thyroid storm (a severe thyrotoxic crisis) is present.

This section includes detailed codes such as E05.00 for thyrotoxicosis with diffuse goiter without crisis, often referred to by synonyms like Graves' disease or toxic diffuse goiter, helping coders identify cases of classic autoimmune hyperthyroidism. Codes like E05.10 and E05.20 refer to toxic single and multinodular thyroid nodules, respectively, with options to specify the presence or absence of a thyrotoxic crisis. The E05.4X series covers thyrotoxicosis factitia, which is caused by excessive thyroid hormone intake. Other specified forms, including ectopic thyroid tissue-related thyrotoxicosis and conditions caused by iodine or medications, are under E05.8X. Lastly, unspecified thyrotoxicosis codes E05.90 and E05.91 are used when the exact type is unclear but symptoms like heart disease or crisis are noted. The inclusion of synonyms such as “thyrotoxic crisis,” “Graves' disease,” and “toxic nodular goiter” alongside the codes helps medical coders accurately select the correct ICD-10 code for hyperthyroidism cases based on clinical presentation.

Questions About This Page

How many billable codes are in the E05 range?

Of the 22 codes in this range, 14 are billable and valid for claim submission from October 1, 2025 through September 30, 2026. Category header codes group them but cannot be reported on claims.

What does the E05 range classify?

The range classifies thyrotoxicosis [hyperthyroidism]. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.

Related References

Source: CMS FY 2026 ICD-10-CM Tabular List and order file, effective October 1, 2025 through September 30, 2026.