2026 ICD-10-CM Diagnosis Code F44.9Dissociative and conversion disorder, unspecified

ICD-10-CM Codes›F01–F99›F40-F48›F44

ICD-10-CM F44.9
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

F44.9 is a billable ICD-10-CM diagnosis code for dissociative and conversion disorder, unspecified. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 880. Coders also document this condition as acute hysterical psychosis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Trauma- and stressor-related disorders.

F44.9 does not risk-adjust for Medicare Advantage under the CMS-HCC V28 model. It still risk-adjusts in the RxHCC Part D (V08) category 133 for payment year 2026.

Code Identity

ICD-10-CM Code
F44.9
Billable Status
Yes — Valid for Submission
Code Describes
Dissociative and conversion disorder, unspecified
Short Description
Dissociative and conversion disorder, unspecified
Same as the full description in the CMS dataset.
Parent Code
F44
Dissociative and conversion disorders

Code Classification

ChapterF01–F99Mental and behavioural disorders
SectionF40-F48Anxiety, dissociative, stress-related, somatoform and other nonpsychotic mental disorders
CategoryF44Dissociative and conversion disorders
This CodeF44.9Dissociative and conversion disorder, unspecified

Medicare Risk Adjustment (HCC)Billing

F44.9 does not risk-adjust for Medicare Advantage under the CMS-HCC V28 model, but it maps to payment categories in the other CMS models shown below.

CMS-HCC V28 (Medicare Advantage Payment Model)
Not mapped
no payment category in the model that pays 100% of MA risk scores
Prior Model (CMS-HCC V24)
Not mapped under V24
this diagnosis newly risk-adjusts under the V28 model
Part D (RxHCC)
RxHCC 133 — Anxiety and Other Psychiatric Disorders
also risk-adjusts in the Part D prescription drug model (V08)

Source: CMS Payment Year 2026 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acute hysterical psychosis
  • Conversion disorder, single episode
  • Dissociation - mental defense mechanism
  • Dissociative disorder
  • Dissociative disorder in remission
  • Dissociative neurological symptom disorder co-occurrent with chorea
  • Dissociative neurological symptom disorder co-occurrent with myoclonus
  • Recurrent conversion disorder
  • Secondary dissociative disorder

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • Dissociative disorder NOS

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR MBD007
Trauma- and stressor-related disorders
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Dissociative Disorder

    a category of psychiatric disorders which are characterized by a disruption in the usually integrated functions of consciousness, memory, identity, and/or perception of the environment.

Patient EducationClinical

Mental Disorders

Mental disorders (or mental illnesses) are conditions that affect your thinking, feeling, mood, and behavior. They may happen over a short period of time or come and go. Some can be chronic (long-lasting). They can affect your ability to relate to others and function each day..

The full article covers:

  • What are mental disorders?
  • What are some types of mental disorders?
  • What causes mental disorders?
  • Who is at risk for mental disorders?
  • How are mental disorders diagnosed?
  • What are the treatments for mental disorders?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert F44.9 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
300.15 Dissociative react NOS
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About F44.9Overview

What is the ICD-10 code for dissociative and conversion disorder, unspecified?

The ICD-10-CM code for dissociative and conversion disorder, unspecified is F44.9 (sometimes written as F449). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

Is F44.9 (Dissociative and conversion disorders) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report dissociative and conversion disorder, unspecified on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does F44.9 group to?

When dissociative and conversion disorder, unspecified is the principal diagnosis on an inpatient stay, it groups to MS-DRG 880 (acute Adjustment Reaction and Psychosocial Dysfunction), which carries a relative weight of 0.9602. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of F44.9?

Under the General Equivalence Mappings, dissociative and conversion disorder, unspecified converts to ICD-9-CM 300.15 (dissociative react NOS). The mapping is approximate, so confirm the match fits the documentation.

Does F44.9 risk-adjust for Medicare Advantage payment?

Not for Medicare Advantage: F44.9 maps to no category in the CMS-HCC V28 model. It still risk-adjusts in the RxHCC Part D (V08) category 133 (Anxiety and Other Psychiatric Disorders).