ICD-10 Code J35.0 – Chronic tonsillitis and adenoiditis (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code J35.0 – Chronic tonsillitis and adenoiditis
What it is
J35.0 identifies chronic inflammation of the tonsils and adenoids. Use it when the record supports a persistent, recurring condition rather than an acute throat infection.
Clinical signs
Typical documentation may note repeated sore throat, enlarged tonsils or adenoids, mouth breathing, snoring, or recurrent throat infections. Clinical features vary; refer to documentation.
When to use this code
Use J35.0 when the clinician documents chronic tonsillitis, chronic adenoiditis, or both together. It also fits follow-up visits for a known longstanding condition when the diagnosis remains active. Check documentation if the note only describes an acute episode or an unspecified upper respiratory complaint.
Do not use for
Do not use this code for acute tonsillitis, peritonsillar abscess, or other separate throat infections. If the record does not clearly support chronic disease, check documentation.
Coding tip
Code J35.0 only when chronicity is stated or clearly documented by the provider.