2026 ICD-10-CM Diagnosis Code T67.9XXSEffect of heat and light, unspecified, sequela
T67.9XXS is a billable ICD-10-CM diagnosis code for effect of heat and light, unspecified, 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 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 922 through 923. The code is exempt from POA reporting. Coders also document this condition as effect of exposure to light. 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
T67.9XXS is exempt from POA reporting on inpatient claims to general acute care hospitals. Review other POA exempt codes.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Effect of exposure to light
- Effects of heat
- Heat exposure
- Thermal injury
- War injury due to heat from nuclear weapon
- War injury due to nuclear weapons
Coding GuidelinesGuidance
The appropriate 7th character is to be added to each code from block Effects of heat and light (T67). 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.
Patient EducationClinical
Heat Illness
Your body normally cools itself by sweating. During hot weather, especially when it is very humid, sweating just isn't enough to cool you off. Your body temperature can rise to dangerous levels and you can develop a heat illness.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert T67.9XXS to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About T67.9XXSOverview
Is T67.9XXS (Effect of heat and light, unspecified) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report effect of heat and light, unspecified, sequela on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character S in T67.9XXS mean?
The final character S makes this a sequela code: it reports a lingering problem that remains after the effect of heat and light, unspecified itself has resolved, not the original event.
What MS-DRG does T67.9XXS group to?
When effect of heat and light, unspecified, sequela 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.
Is T67.9XXS 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 effect of heat and light, unspecified, sequela on inpatient claims.
What is the ICD-9 equivalent of T67.9XXS?
Under the General Equivalence Mappings, effect of heat and light, unspecified, sequela converts to ICD-9-CM 909.4 (late eff cert ext cause). 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.
