ICDcodes.org
FY2027

T25.412ACorrosion of unspecified degree of left ankle, initial encounter

BillableUnspecified

Is T25.412A billable?

Yes, but T25.412A is an unspecified code. T25.412A is a valid, billable ICD-10-CM code for encounters from October 1, 2026 through September 30, 2027. However, T25.412A is an unspecified or catch-all code. Payers apply additional scrutiny to unspecified codes and many deny them when the medical record supports a more specific option, so check the documentation before selecting T25.412A — the more specific alternatives are listed below.

T25.412A at a glance

CodeT25.412A
DescriptionCorrosion of unspecified degree of left ankle, initial encounter
BillableYes
Code setICD-10-CM FY2027
Valid for encountersOctober 1, 2026 – September 30, 2027
7th character "A"initial encounter

What does the 7th character "A" mean in T25.412A?

In T25.412A, the 7th character A means initial encounter. The 7th character is required for T25.412A to be a valid, complete code.

Same condition, different episode of care — switch the 7th character:

Which MS-DRGs does T25.412A group to?

T25.412A sits in MDC 22 and helps define the logic of 1 MS-DRG (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.

  • 935Non-Extensive Burnsmedical

How is T25.412A listed in the Alphabetic Index?

The Alphabetic Index lists these routes under T25.412, the nearest indexed parent of T25.412A. Use them to find the family, then select the specific code.

  • Corrosionankleleft (injury) (acid) (caustic) (chemical) (lime) (external) (internal)

Code first — inherited from T25.4

The underlying condition below must be sequenced before T25.412A. T25.412A 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 T25.412A to fully describe the condition. T25.412A 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 T25.412A to fully describe the condition. T25.412A is sequenced first.

  • code from category T31 or T32 to identify extent of body surface involved

Use additional code — inherited from T25.4

Report an additional code alongside T25.412A to fully describe the condition. T25.412A 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 T25.412A, but a patient may have both at the same time. When documentation supports it, T25.412A and the excluded code may both be reported.

  • birth trauma (P10-P15)
  • obstetric trauma (O70-O71)

How long has T25.412A existed?

T25.412A 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.