2026 ICD-10-CM Diagnosis Code T68.XXXAHypothermia, initial encounter

ICD-10-CM Codes›S00–T88›T66-T78›T68

ICD-10-CM T68.XXXA
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

T68.XXXA is a billable ICD-10-CM diagnosis code for hypothermia, initial encounter. The 7th character A marks it as an initial encounter code, used while the patient is receiving active treatment. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 922 through 923. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Effect of other external causes, initial encounter.

Code Identity

ICD-10-CM Code
T68.XXXA
Billable Status
Yes — Valid for Submission
Code Describes
Hypothermia, initial encounter
Short Description
Hypothermia, initial encounter
Same as the full description in the CMS dataset.
Parent Code
T68
Hypothermia

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionT66-T78Other and unspecified effects of external causes
CategoryT68Hypothermia
This CodeT68.XXXAHypothermia, initial encounter

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Accidental hypothermia in elderly person
  • Body temperature below reference range
  • Effects of exposure to extreme temperature
  • Hypothermia
  • Hypothermia - accidental
  • Hypothermia caused by cold environment
  • Immersion hypothermia
  • Thrombocytopenia due to hypothermia
  • Unplanned perioperative hypothermia

Coding GuidelinesGuidance

The appropriate 7th character is to be added to each code from block Hypothermia (T68). 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 2026, published by CMS and the National Center for Health Statistics.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR INJ021
Effect of other external causes, initial encounter
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Hypothermia

Cold weather can affect your body in different ways. You can get frostbite, which is an injury to the body that is caused by freezing. Your body can also lose heat faster than you can produce it. That can cause hypothermia, or abnormally low body temperature. It can make you sleepy, confused, and clumsy.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert T68.XXXA to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
991.6 Hypothermia
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About T68.XXXAOverview

Is T68.XXXA (Hypothermia) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report hypothermia, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What does the 7th character A in T68.XXXA mean?

The final character A marks the initial encounter: use it while the patient is receiving active treatment for hypothermia, such as an emergency visit or first evaluation.

What MS-DRG does T68.XXXA group to?

When hypothermia, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 922, 923, with relative weights from 1.0177 to 1.7494 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of T68.XXXA?

Under the General Equivalence Mappings, hypothermia, initial encounter converts to ICD-9-CM 991.6 (hypothermia). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.