ICD-10 Code E08.621 – Diabetes mellitus due to underlying condition with foot ulcer (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code E08.621 – Diabetes mellitus due to underlying condition with foot ulcer
What it is
This code identifies diabetes caused by another underlying condition, complicated by a foot ulcer. Use it when the record clearly links the diabetes to the secondary cause and the ulcer to the diabetic condition.
Clinical signs
Typical findings include an open sore on the foot with surrounding tissue breakdown, often with impaired healing. Clinical features vary; refer to documentation for the underlying condition and whether the ulcer is diabetic in origin.
When to use this code
Use E08.621 when the provider documents diabetes due to another condition and a foot ulcer is present. The chart should support both the secondary diabetes and the ulcer relationship. Add any documented ulcer severity or site details with the appropriate additional codes.
Do not use for
Do not use this code if the diabetes is not due to an underlying condition or if the foot ulcer is unrelated to diabetes. Check documentation when the cause of diabetes or ulcer relationship is unclear.
Coding tip
Verify the underlying condition, then code the ulcer separately and as specifically as the documentation allows.