ICD-10-CM 2027 diagnosis code
Z91.85Personal history of military service
Z91.85 is a valid, billable ICD-10-CM code for personal history of military service. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.
Code last changed in FY2024 (effective October 1, 2023). Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data
About Z91.85
Z91.85 is the ICD-10-CM diagnosis code for personal history of military service. It belongs to category Z91 (personal risk factors, not elsewhere classified), block Z77-Z99 (persons with potential health hazards related to family and personal history and certain conditions influencing health status) and chapter 21 (factors influencing health status and contact with health services). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.
Within Z91.8 (other specified personal risk factors, not elsewhere classified), Z91.85 is specifically for personal history of military service. Related codes cover history of falling (Z91.81), personal history of military deployment (Z91.82), Wandering in diseases classified elsewhere (Z91.83), oral health risk factors (Z91.84) and other specified personal risk factors, not elsewhere classified (Z91.89).
The conditions in its Excludes2 note aren't part of Z91.85, but may be coded alongside it if the patient has both: personal history of military deployment (Z91.82).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 951 (Other Factors Influencing Health Status, relative weight 0.5577), in MDC 23 (Factors Influencing Health Status and Other Contacts with Health Services), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
It is not acceptable as the principal diagnosis for an inpatient stay; it may be reported as a secondary diagnosis.
It is exempt from present-on-admission (POA) reporting, so no POA indicator is required.
It was added in FY2024, effective October 1, 2023.
Coding notes
- Personal history of serving in the armed forces
- Personal history of veteran
- personal history of military deployment (Z91.82)
Notes that apply from higher levels
Instructions written at a parent level also apply to Z91.85.
› From Z91 Personal risk factors, not elsewhere classified
Broader instructions also apply from Z77-Z99 Persons with potential health hazards related to family and personal history and certain conditions influencing health status and Chapter 21: Factors influencing health status and contact with health services.
Alphabetic index entries
1 entriesTerms in the official ICD-10-CM index that lead to Z91.85.
Codes whose notes reference Z91.85
- Z91.82Excludes2
MS-DRG v44.0 grouping
All DRGs →Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.
MDC 23 · Factors Influencing Health Status and Other Contacts with Health Services
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2024 (effective 10/1/2023): Added
- No changes since FY2024.
Common questions about Z91.85
Is Z91.85 billable?
- Yes. Z91.85 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can Z91.85 be used as a principal diagnosis?
- No. It is not acceptable as the principal diagnosis for an inpatient stay; it may be reported as a secondary diagnosis.
Is Z91.85 a CC or MCC?
- No. Z91.85 is neither a CC nor an MCC under MS-DRG v44.0.
What DRG does Z91.85 group to?
- Z91.85 is used in the MS-DRG v44.0 logic for MS-DRG 951 (Other Factors Influencing Health Status). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.