ICD-10 Code I80.25 – Phlebitis and thrombophlebitis of calf muscular vein (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code I80.25 – Phlebitis and thrombophlebitis of calf muscular vein
What it is
This code identifies inflammation of a calf muscular vein with associated clot formation, usually in the gastrocnemius or soleal veins. Use it when documentation specifically names a muscular vein thrombosis in the calf.
Clinical signs
Clinical features vary; refer to documentation. Commonly recorded findings include localized calf pain, tenderness, swelling, or warmth, but diagnosis should be supported by the provider’s assessment and imaging when available.
When to use this code
Use I80.25 when the provider documents phlebitis or thrombophlebitis in a calf muscular vein, not just a general leg vein. It may also fit when imaging or a specialist note clearly identifies a muscular calf vein clot. Check documentation if the vein location is unclear.
Do not use for
Do not use this code for superficial thrombophlebitis, deep vein thrombosis in a different leg vein, or unspecified lower-extremity thrombosis. If the record only says “DVT” or “leg clot,” check documentation for the exact site.
Coding tip
Confirm that the calf muscular vein is named in the record; the anatomic site drives correct code selection.