External cause status (Y99) ICD-10-CM
The Y99 code range covers external cause status with 6 ICD-10-CM diagnosis codes. 5 of them are billable and valid for claim submission in fiscal year 2026, and the category headers group them but cannot themselves be billed.
- 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.
Codes in the Y99 Range 6 codes · 5 billable
About the Y99 Code Range
ICD-10 code Y99 represents the category for external cause status, which records the activity status of a person at the time of an injury or external cause event. This classification helps specify whether the affected individual was engaged in work, military service, volunteer work, or other activities when the incident occurred.
These codes are used to detail the context of injuries or external causes, providing clarity for medical coders in billing and documentation. For example, Y99.0 refers to accidents occurring during civilian work-related activities, encompassing situations like drowning during underwater construction or overwork-related deaths. Similarly, Y99.1 captures incidents tied to military activities, including accidents during training or post-traumatic stress disorder following combat. Y99.2 denotes volunteer activities, while Y99.8 covers other external cause statuses such as accidental drownings during recreational activities like fishing or hunting. When the specific activity status is unknown, Y99.9 is used as an unspecified code. Understanding these distinctions is essential for correctly applying the ICD-10 code for external cause status in medical records and claims.
Questions About This Page
How many billable codes are in the Y99 range?
Of the 6 codes in this range, 5 are billable and valid for claim submission from October 1, 2025 through September 30, 2026. Category header codes group them but cannot be reported on claims.
What does the Y99 range classify?
The range classifies external cause status. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2026 ICD-10-CM Tabular List and order file, effective October 1, 2025 through September 30, 2026.
