2026 ICD-10-CM Diagnosis Code Y99External cause status

ICD-10-CM Codes›V01–Y99›Y90-Y99›Y99

ICD-10-CM Y99
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

Y99 is a non-billable ICD-10-CM category code for external cause status, so it cannot be submitted on claims. Use a more specific code from this category instead, such as Y99.0, Y99.1, Y99.2, and Y99.8.

Code Identity

ICD-10-CM Code
Y99
Billable Status
No — Non-Billable Category
Code Describes
External cause status
Chapter
Y90-Y99
Supplementary factors related to causes of morbidity classified elsewhere

Code Classification

ChapterV01–Y99External causes of morbidity and mortality
SectionY90-Y99Supplementary factors related to causes of morbidity classified elsewhere
CategoryY99External cause status
This CodeY99External cause status

Specific Coding for External cause statusOverview

Non-specific codes like Y99 require more characters. Use one of these billable codes instead:

  • Use Y99.0 for Civilian activity done for income or pay

  • Use Y99.1 for Military activity

  • Use Y99.2 for Volunteer activity

  • Use Y99.8 for Other external cause status

  • Use Y99.9 for Unspecified external cause status

Tabular List NotesGuidance

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

  • A single code from category Y99 should be used in conjunction with the external cause codes assigned to a record to indicate the status of the person at the time the event occurred.

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 Y99Overview

Is Y99 (External cause status) a billable code?

No. This is a category header that groups the codes for external cause status, and headers cannot be submitted on claims. Claims for external cause status need a more specific code from this category, such as Y99.0, Y99.1, and Y99.2.