2026 ICD-10-CM Diagnosis Code F40.9Phobic anxiety disorder, unspecified

ICD-10-CM Codes›F01–F99›F40-F48›F40

ICD-10-CM F40.9
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

F40.9 is a billable ICD-10-CM diagnosis code for phobic anxiety disorder, unspecified. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Anxiety and fear-related disorders.

Code Identity

ICD-10-CM Code
F40.9
Billable Status
Yes — Valid for Submission
Code Describes
Phobic anxiety disorder, unspecified
Short Description
Phobic anxiety disorder, unspecified
Same as the full description in the CMS dataset.
Parent Code
F40
Phobic anxiety disorders

Code Classification

ChapterF01–F99Mental and behavioural disorders
SectionF40-F48Anxiety, dissociative, stress-related, somatoform and other nonpsychotic mental disorders
CategoryF40Phobic anxiety disorders
This CodeF40.9Phobic anxiety disorder, unspecified

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acute vestibular syndrome
  • Acute vestibular syndrome due to anxiety and fear
  • Anxiety and fear
  • Fears delivery procedure
  • Insomnia disorder related to another mental disorder
  • Insomnia due to anxiety and fear
  • Phobia
  • Phobic disorder
  • Prenatal finding
  • Reduced level of fear
  • Specific fear
  • Terrified

Tabular List NotesGuidance

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

Inclusion Terms

  • Phobia NOS
  • Phobic state NOS

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Disorder(of)
      • anxiety
        • phobic
    • Disorder(of)
      • psychogenic NOS
        • phobic
    • Fear complex or reaction
    • Neurosis, neurotic
      • phobic
    • Phobia, phobic
    • Phobia, phobic
      • reaction
    • Phobia, phobic
      • state
    • Reaction
      • fear
    • Reaction
      • phobic
    • State(of)
      • phobic

Clinical ClassificationClinical

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

CCSR MBD005
Anxiety and fear-related disorders
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Phobias

A phobia is a type of anxiety disorder. It is a strong, irrational fear of something that poses little or no real danger.

Read the full article at MedlinePlus

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

Convert F40.9 to ICD-9-CMHistory

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

ICD-9-CM
300.20 Phobia 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 F40.9Overview

Is F40.9 (Phobic anxiety disorders) a billable code?

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

What is the ICD-9 equivalent of F40.9?

Under the General Equivalence Mappings, phobic anxiety disorder, unspecified converts to ICD-9-CM 300.20 (phobia NOS). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.