T25.639 — Corrosion of second degree of unspecified toe(s) (nail)
Is T25.639 billable?
No — T25.639 is a non-billable header code. T25.639 groups more specific codes and cannot be submitted on a claim. A valid ICD-10-CM code must be reported at the highest level of specificity available in its branch. Select one of the 3 billable codes beneath T25.639.
T25.639 at a glance
| Code | T25.639 |
|---|---|
| Description | Corrosion of second degree of unspecified toe(s) (nail) |
| Billable | No — header code |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
How is T25.639 listed in the Alphabetic Index?
These are the routes through the Alphabetic Index that lead to T25.639. They show the wording a clinician may have documented, which often differs from the Tabular description.
- Corrosion › toe › second degree (injury) (acid) (caustic) (chemical) (lime) (external) (internal)
Code first — inherited from T25.6
The underlying condition below must be sequenced before T25.639. T25.639 describes a manifestation and cannot be the principal or first-listed diagnosis.
- (T51-T65) to identify chemical and intent
Use additional code — inherited from Chapter 19
Report an additional code alongside T25.639 to fully describe the condition. T25.639 is sequenced first.
- code to identify any retained foreign body, if applicable (Z18.-)
Use additional code — inherited from T20-T25
Report an additional code alongside T25.639 to fully describe the condition. T25.639 is sequenced first.
Use additional code — inherited from T25.6
Report an additional code alongside T25.639 to fully describe the condition. T25.639 is sequenced first.
- external cause code to identify place (Y92)
Excludes2 — not included here — inherited from Chapter 19
The conditions below are not part of T25.639, but a patient may have both at the same time. When documentation supports it, T25.639 and the excluded code may both be reported.
What codes fall under T25.639? (3)
How long has T25.639 existed?
T25.639 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.