2027 ICD-10-CM Diagnosis Code T33.90XSSuperficial frostbite of unspecified sites, sequela
T33.90XS is a billable ICD-10-CM diagnosis code for superficial frostbite of unspecified sites, sequela. The 7th character S marks it as a sequela code, which reports a problem that remains after the original condition has resolved. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 922 through 923. The code is exempt from POA reporting. Coders also document this condition as cold burn. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Effect of other external causes, sequela.
Code Identity
Code Classification
Present on Admission (POA)Billing
T33.90XS is exempt from POA reporting on inpatient claims to general acute care hospitals. Review the other POA exempt codes in Frostbite (T33-T34).
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Cold burn
- Frostbite
- Frostbite alopecia
- Frostbite of multiple body regions
- Superficial frostbite
- Superficial frostbite involving multiple body regions
- Superficial injuries involving multiple body regions
Coding GuidelinesGuidance
The appropriate 7th character is to be added to each code from block Superficial frostbite (T33). Use the following options for the applicable episode of care:
- A - initial encounter
- D - subsequent encounter
- S - sequela
Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2027, published by CMS and the National Center for Health Statistics.
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to T33.90XS: its own notes plus those printed at T33, block T33-T34, and Chapter 19. A note printed at a category, block or chapter applies to every code under it.
Includes
Further defines, or gives examples of, the content of the category.
- frostbite with partial thickness skin loss
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.
Use Additional Code
Add a second code, after this one, to fully describe the condition.
- code to identify any retained foreign body, if applicable (Z18.-)
Notes
General instructions on how these codes are used.
- Use secondary code(s) from Chapter 20, External causes of morbidity, to indicate cause of injury. Codes within the T section that include the external cause do not require an additional external cause code
- The chapter uses the S-section for coding different types of injuries related to single body regions and the T-section to cover injuries to unspecified body regions as well as poisoning and certain other consequences of external causes.
7th Character
Every code in the category takes a 7th character from the listed values, with the placeholder X filling any empty positions before it.
- The appropriate 7th character is to be added to each code from category T33
- Ainitial encounter
- Dsubsequent encounter
- Ssequela this code
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Frostbite
damage to tissues as the result of low environmental temperatures.
Patient EducationClinical
Frostbite
Frostbite is an injury to the body that is caused by freezing. It most often affects the nose, ears, cheeks, chin, fingers, or toes. Frostbite can permanently damage the body, and severe cases can lead to amputation.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert T33.90XS to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About T33.90XSOverview
What is the ICD-10 code for superficial frostbite of unspecified sites, sequela?
The ICD-10-CM code for superficial frostbite of unspecified sites, sequela is T33.90XS (sometimes written as T3390XS). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is T33.90XS (Superficial frostbite of unspecified sites) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report superficial frostbite of unspecified sites, sequela on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What does the 7th character S in T33.90XS mean?
The final character S makes this a sequela code: it reports a lingering problem that remains after the superficial frostbite of unspecified sites itself has resolved, not the original event.
What MS-DRG does T33.90XS group to?
When superficial frostbite of unspecified sites, sequela is the principal diagnosis on an inpatient stay, it groups to MS-DRG 923, 922, with relative weights from 0.9980 to 1.6248 depending on complications. Higher weights mean higher Medicare reimbursement.
Is T33.90XS exempt from POA reporting?
Yes. CMS lists this code among those exempt from present on admission reporting, so hospitals do not assign a POA indicator for superficial frostbite of unspecified sites, sequela on inpatient claims. The code appears in the Frostbite (T33-T34) range of the CMS exempt list.
