ICD-10 Code E04.1 – Nontoxic single thyroid nodule (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code E04.1 – Nontoxic single thyroid nodule
What it is
This code identifies a single thyroid nodule that is not producing excess thyroid hormone. Use it when the record describes one discrete thyroid lump without evidence of toxic goiter or hyperthyroidism.
Clinical signs
Clinical features vary; refer to documentation. A nodule may be found on physical exam, ultrasound, or other imaging, and patients are often asymptomatic unless the mass causes local neck symptoms.
When to use this code
Use E04.1 when the provider documents a solitary thyroid nodule and specifically indicates it is nontoxic. This applies whether the finding is incidental or evaluated for enlargement, compression, or malignancy risk. Do not assume thyroid function status; it must be documented.
Do not use for
Do not use this code for toxic thyroid nodules, multinodular goiter, or unspecified thyroid nodules. If the note does not clearly state a single nodule, check documentation.
Coding tip
Confirm both “single” and “nontoxic” in the provider note before assigning E04.1.