ICD-10 Code K13.79 – Other lesions of oral mucosa (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code K13.79 – Other lesions of oral mucosa
What it is
K13.79 identifies other abnormal lesions of the oral mucosa that do not fit a more specific diagnosis. Use it for documented mucosal changes in the mouth when the exact lesion type is not named.
Clinical signs
Clinical features vary; refer to documentation. Commonly, records describe visible oral mucosal lesions, such as patches, bumps, ulcers, or areas of irritation that require further characterization.
When to use this code
Use this code when the clinician documents an oral mucosal lesion but does not specify a more precise condition. It may also fit cases where the lesion is described only as “other” or remains unclassified after evaluation.
Make sure the note supports a mucosal lesion inside the mouth, not a skin or lip-only finding. If the documentation names a specific disorder, code that condition instead.
Do not use for
Do not use K13.79 when the chart identifies a more specific oral diagnosis, such as a defined ulcerative, inflammatory, or neoplastic lesion. Check documentation for the exact lesion type.
Coding tip
Code the most specific oral lesion documented; reserve K13.79 for nonspecific or unclassified oral mucosal findings.