---
title: "ICD-10-CM F84.9: Pervasive developmental disorder… | BillingBrief"
description: "Use F84.9 when a pervasive developmental disorder is documented without a type; it includes atypical autism. If autistic disorder, Rett's syndrome…"
canonical: "https://billingbrief.com/icd10/f84.9/"
language: "en"
---

# F84.9 Pervasive developmental disorder, unspecified

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

Use F84.9 when a pervasive developmental disorder is documented without a type; it includes atypical autism. If autistic disorder, Rett's syndrome, childhood disintegrative disorder or Asperger's syndrome is documented, use F84.0, F84.2, F84.3 or F84.5.

## 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

-   Atypical autism

### Code also

A second code may be needed. Sequencing depends on the encounter.

-   any associated medical condition and intellectual disabilities

## Related codes

-   [`F84.0` Autistic disorder ICD-10-CM](https://billingbrief.com/icd10/f84.0/)
-   [`F84.2` Rett's syndrome ICD-10-CM](https://billingbrief.com/icd10/f84.2/)
-   [`F84.3` Other childhood disintegrative disorder ICD-10-CM](https://billingbrief.com/icd10/f84.3/)
-   [`F84.5` Asperger's syndrome ICD-10-CM](https://billingbrief.com/icd10/f84.5/)
-   [`F84.8` Other pervasive developmental disorders ICD-10-CM](https://billingbrief.com/icd10/f84.8/)

## Common questions

### Is F84.9 a billable code?

Yes. F84.9 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

F84 Pervasive developmental 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/).