ICD-10 Code K60.31 – Anal fistula, simple (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code K60.31 – Anal fistula, simple
What it is
K60.31 identifies a simple anal fistula, an abnormal tunnel between the anal canal and nearby skin. Use this code when documentation clearly states the fistula is simple and not described as complex or recurrent.
Clinical signs
Typical findings include persistent drainage near the anus, local irritation, pain, or swelling. Clinical features vary; refer to documentation, especially for the fistula’s location, tract description, and whether an abscess is present.
When to use this code
Use K60.31 when the provider documents a simple anal fistula on the encounter record, operative note, or assessment. It also fits follow-up visits when the condition remains active and is still being managed. Check documentation if the note does not clearly distinguish simple from complex disease.
Do not use for
Do not use this code for anal fissure, hemorrhoids, or perianal abscess without a documented fistula. If the record describes a complex, recurrent, or Crohn’s-related fistula, verify the correct code in the chart.
Coding tip
Assign K60.31 only when the provider explicitly documents “simple” anal fistula; otherwise, check documentation for a more specific fistula code.