F43.9 – Reaction to severe stress, unspecified
ICD-10-CM 2027 diagnosis code · Anxiety, dissociative, stress-related, somatoform and other nonpsychotic mental disorders
ICD-10-CM code
F43.9
- Code
F43.9(claims format:F439)- Description
- Reaction to severe stress, unspecified
- Billable
- Yes – valid for HIPAA-covered transactions
- Valid for
- Dates of service October 1, 2026 – September 30, 2027 (FY2027)
- Chapter
- 5. Mental, Behavioral and Neurodevelopmental disorders (F01-F99)
- Block
- F40-F48 Anxiety, dissociative, stress-related, somatoform and other nonpsychotic mental disorders
- Parent codes
- F43
Notes for F43.9
Applicable to:
- Trauma and stressor-related disorder, NOS
- Unspecified trauma and stressor-related disorder
Index terms for F43.9
Entries in the ICD-10-CM alphabetic index that lead to this code:
Related codes in F43
Frequently asked questions
What is ICD-10 code F43.9?
F43.9 is the ICD-10-CM code for reaction to severe stress, unspecified, in the block F40-F48 (Anxiety, dissociative, stress-related, somatoform and other nonpsychotic mental disorders).
Is F43.9 a billable code?
Yes. F43.9 is a billable/specific code that can be used to indicate a diagnosis for reimbursement purposes.
What category does F43.9 belong to?
It belongs to category F43 – Reaction to severe stress, and adjustment disorders.
Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.