---
title: "ICD-10-CM F43.9: Reaction to severe stress, unspecified | BillingBrief"
description: "ICD-10-CM code F43.9: Reaction to severe stress, unspecified. Category, related codes, and the official source, in plain English."
canonical: "https://billingbrief.com/icd10/f43.9/"
language: "en"
---

# F43.9 Reaction to severe stress, unspecified

ICD-10-CM · [CMS code reference](#source)

**Official ICD-10-CM description:** Reaction to severe stress, unspecified

## Related codes

-   [`F43.0` Acute stress reaction ICD-10-CM](https://billingbrief.com/icd10/f43.0/)
-   [`F43.10` Post-traumatic stress disorder, unspecified ICD-10-CM](https://billingbrief.com/icd10/f43.10/)
-   [`F43.11` Post-traumatic stress disorder, acute ICD-10-CM](https://billingbrief.com/icd10/f43.11/)
-   [`F43.12` Post-traumatic stress disorder, chronic ICD-10-CM](https://billingbrief.com/icd10/f43.12/)
-   [`F43.20` Adjustment disorder, unspecified ICD-10-CM](https://billingbrief.com/icd10/f43.20/)
-   [`F43.21` Adjustment disorder with depressed mood ICD-10-CM](https://billingbrief.com/icd10/f43.21/)
-   [`F43.22` Adjustment disorder with anxiety ICD-10-CM](https://billingbrief.com/icd10/f43.22/)
-   [`F43.23` Adjustment disorder with mixed anxiety and depressed mood ICD-10-CM](https://billingbrief.com/icd10/f43.23/)

## Common questions

### Is F43.9 a billable code?

Yes. F43.9 is a billable ICD-10-CM code in the ICD-10-CM FY2027 (effective October 1, 2026) code set.

## From the source

Official description from [CMS](https://www.cms.gov/medicare/coding-billing/icd-10-codes).
ICD-10-CM FY2027 (effective October 1, 2026).

Code set

ICD-10-CM

Category

F43 Reaction to severe stress, and adjustment disorders

Chapter

Mental, behavioral and neurodevelopmental disorders

Billable

Yes

Educational reference only. Not medical, legal, or billing advice. Always check the current official code set and payer policy before you bill. [About BillingBrief and our sources](https://billingbrief.com/about/).