---
title: "ICD-10-CM F51.5: Nightmare disorder | BillingBrief"
description: "ICD-10-CM code F51.5: Nightmare disorder. Category, related codes, and the official source, in plain English."
canonical: "https://billingbrief.com/icd10/f51.5/"
language: "en"
---

# F51.5 Nightmare disorder

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

**Official ICD-10-CM description:** Nightmare disorder

## Coding notes

From the ICD-10-CM FY2027 (effective October 1, 2026) tabular list. Notes on a parent code or category apply here too.

### Also covers

-   Dream anxiety disorder

### Excludes2

Not part of this code, but both can be coded when both are documented.

-   organic sleep disorders (G47.-)

## Related codes

-   [`F51.11` Primary hypersomnia ICD-10-CM](https://billingbrief.com/icd10/f51.11/)
-   [`F51.12` Insufficient sleep syndrome ICD-10-CM](https://billingbrief.com/icd10/f51.12/)
-   [`F51.13` Hypersomnia due to other mental disorder ICD-10-CM](https://billingbrief.com/icd10/f51.13/)
-   [`F51.19` Other hypersomnia not due to a substance or known physiological condition ICD-10-CM](https://billingbrief.com/icd10/f51.19/)
-   [`F51.3` Sleepwalking \[somnambulism\] ICD-10-CM](https://billingbrief.com/icd10/f51.3/)
-   [`F51.4` Sleep terrors \[night terrors\] ICD-10-CM](https://billingbrief.com/icd10/f51.4/)
-   [`F51.8` Other sleep disorders not due to a substance or known physiological condition ICD-10-CM](https://billingbrief.com/icd10/f51.8/)
-   [`F51.9` Sleep disorder not due to a substance or known physiological condition, unspecified ICD-10-CM](https://billingbrief.com/icd10/f51.9/)

## Common questions

### Is F51.5 a billable code?

Yes. F51.5 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

F51 Sleep disorders not due to a substance or known physiological condition

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/).