2026 ICD-10-CM Diagnosis Code Z59.11Inadequate housing environmental temperature

ICD-10-CM Codes›Z00–Z99›Z55-Z65›Z59

ICD-10-CM Z59.11
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

Z59.11 is a billable ICD-10-CM diagnosis code for inadequate housing environmental temperature. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). The code is not accepted as a principal diagnosis by the Medicare Code Editor and exempt from POA reporting. Coders also document this condition as housing unsuited to needs. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Socioeconomic/psychosocial factors.

Code Identity

ICD-10-CM Code
Z59.11
Billable Status
Yes — Valid for Submission
Code Describes
Inadequate housing environmental temperature
Short Description
Inadequate housing environmental temperature
Same as the full description in the CMS dataset.
Parent Code
Z59.1
Inadequate housing

Code Classification

ChapterZ00–Z99Factors influencing health status and contact with health services
SectionZ55-Z65Persons with potential health hazards related to socioeconomic and psychosocial circumstances
CategoryZ59Problems related to housing and economic circumstances
This CodeZ59.11Inadequate housing environmental temperature

Code EditsBilling

Medicare Code Editor checks that affect claim validity for Z59.11.

Unacceptable principal diagnosis
There are selected codes that describe a circumstance which influences an individual's health status but not a current illness or injury, or codes that are not specific manifestations but may be due to an underlying cause. These codes are considered unacceptable as a principal diagnosis.

Present on Admission (POA)Billing

Z59.11 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.

  • Housing unsuited to needs
  • Lack of cooling in house
  • Lack of heat in house
  • No heating facilities in residence

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • Lack of air conditioning
  • Lack of heating

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Inadequate, inadequacy
      • environment, household
    • Inadequate, inadequacy
      • housing
        • environmental temperature
    • Inadequate, inadequacy
      • housing
        • heating
    • Lack of
      • air conditioning
    • Lack of
      • heating
    • Person(with)
      • living (in)
        • without
          • adequate housing
            • air conditioning
    • Person(with)
      • living (in)
        • without
          • adequate housing
            • environmental temperature
    • Person(with)
      • living (in)
        • without
          • adequate housing
            • heating

Clinical ClassificationClinical

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

CCSR FAC019
Socioeconomic/psychosocial factors
Default principal diagnosis: inpatient No · outpatient No

Code History & ChangesHistory

Replacement Z59.11 replaces the following previously assigned code(s):

  • Z59.1 - Inadequate housing
FY 2024AddedAdded to the ICD-10-CM code setEffective October 1, 2023.
FY 2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About Z59.11Overview

Is Z59.11 (Inadequate housing) a billable code?

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

Can Z59.11 be a principal diagnosis?

No. The Medicare Code Editor rejects this code as a principal diagnosis because inadequate housing environmental temperature describes a circumstance that influences health status rather than a current illness. Report it as a secondary diagnosis.

Is Z59.11 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 inadequate housing environmental temperature on inpatient claims.