ICD-10 Code J03.00 – Acute streptococcal tonsillitis, unspecified (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code J03.00 – Acute streptococcal tonsillitis, unspecified
What it is
This code identifies an acute infection of the tonsils caused by streptococcal bacteria, when the record does not specify the streptococcal group. Use it for a documented strep tonsillitis diagnosis, not for nonspecific sore throat alone.
Clinical signs
Typical findings include sudden sore throat, enlarged or inflamed tonsils, fever, and painful swallowing. Clinical features vary; refer to documentation, especially when the note confirms streptococcal infection without further detail.
When to use this code
Use this code when the clinician documents acute streptococcal tonsillitis and does not identify the organism beyond “streptococcal” or “unspecified.” It also fits when the encounter is focused on the acute tonsillar infection itself. If the documentation names a different throat diagnosis, check documentation before assigning this code.
Do not use for
Do not use this code for viral pharyngitis, chronic tonsillitis, or simple sore throat without a documented streptococcal cause. Do not use it when the record specifies a different streptococcal condition and a more precise code is available.
Coding tip
Code from the provider’s exact wording and confirm whether “strep throat” is documented as tonsillitis, pharyngitis, or both.