T20.79XA — Corrosion of third degree of multiple sites of head, face, and neck, initial encounter
Is T20.79XA billable?
Yes — T20.79XA is billable for FY2027. T20.79XA is a valid, billable ICD-10-CM code at the highest level of specificity in its branch. T20.79XA may be submitted for encounters from October 1, 2026 through September 30, 2027.
T20.79XA at a glance
| Code | T20.79XA |
|---|---|
| Description | Corrosion of third degree of multiple sites of head, face, and neck, initial encounter |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
| 7th character "A" | initial encounter |
What does the 7th character "A" mean in T20.79XA?
In T20.79XA, the 7th character A means initial encounter. The 7th character is required for T20.79XA to be a valid, complete code.
Same condition, different episode of care — switch the 7th character:
Which MS-DRGs does T20.79XA group to?
T20.79XA sits in MDC 22 and helps define the logic of 2 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 927Extensive Burns or Full Thickness Burns with MV >96 Hours with Skin Graftsurgical
- 933Extensive Burns or Full Thickness Burns with MV >96 Hours without Skin Graftmedical
As a secondary diagnosis, T20.79XA is a complication or comorbidity (CC), which can move a stay into a higher-paying DRG. It also carries Hospital-Acquired Condition category 05.
How is T20.79XA listed in the Alphabetic Index?
The Alphabetic Index lists these routes under T20.79, the nearest indexed parent of T20.79XA. Use them to find the family, then select the specific code.
- Corrosion › head › multiple sites › third degree (injury) (acid) (caustic) (chemical) (lime) (external) (internal)
Code first — inherited from T20.7
The underlying condition below must be sequenced before T20.79XA. T20.79XA 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 T20.79XA to fully describe the condition. T20.79XA 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 T20.79XA to fully describe the condition. T20.79XA is sequenced first.
Use additional code — inherited from T20.7
Report an additional code alongside T20.79XA to fully describe the condition. T20.79XA 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 T20.79XA, but a patient may have both at the same time. When documentation supports it, T20.79XA and the excluded code may both be reported.
Excludes2 — not included here — inherited from T20
The conditions below are not part of T20.79XA, but a patient may have both at the same time. When documentation supports it, T20.79XA and the excluded code may both be reported.
How long has T20.79XA existed?
T20.79XA 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.