T33.99XA — Superficial frostbite of other sites, initial encounter
Is T33.99XA billable?
Yes — T33.99XA is billable for FY2027. T33.99XA is a valid, billable ICD-10-CM code at the highest level of specificity in its branch. T33.99XA may be submitted for encounters from October 1, 2026 through September 30, 2027.
T33.99XA at a glance
| Code | T33.99XA |
|---|---|
| Description | Superficial frostbite of other sites, 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 T33.99XA?
In T33.99XA, the 7th character A means initial encounter. The 7th character is required for T33.99XA to be a valid, complete code.
Same condition, different episode of care — switch the 7th character:
Which MS-DRGs does T33.99XA group to?
T33.99XA sits in MDC 21 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.
- 922Other Injury, Poisoning and Toxic Effect Diagnoses with MCCmedical
- 923Other Injury, Poisoning and Toxic Effect Diagnoses without MCCmedical
As a secondary diagnosis, T33.99XA 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 T33.99XA listed in the Alphabetic Index?
The Alphabetic Index lists these routes under T33.99, the nearest indexed parent of T33.99XA. Use them to find the family, then select the specific code.
- Frostbite › leg (superficial)
- Frostbite › specified site NEC (superficial)
- Frostbite › trunk (superficial)
- Frostbite › limb › lower (superficial)
Inclusion terms
Alternative wording in documentation that is classified to T33.99XA.
- Superficial frostbite of leg NOS
- Superficial frostbite of trunk NOS
Use additional code — inherited from Chapter 19
Report an additional code alongside T33.99XA to fully describe the condition. T33.99XA is sequenced first.
- code to identify any retained foreign body, if applicable (Z18.-)
Excludes2 — not included here — inherited from Chapter 19
The conditions below are not part of T33.99XA, but a patient may have both at the same time. When documentation supports it, T33.99XA and the excluded code may both be reported.
Excludes2 — not included here — inherited from T33-T34
The conditions below are not part of T33.99XA, but a patient may have both at the same time. When documentation supports it, T33.99XA and the excluded code may both be reported.
How long has T33.99XA existed?
T33.99XA 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.