2026 ICD-10-CM Diagnosis Code F40.240Claustrophobia

ICD-10-CM Codes›F01–F99›F40-F48›F40

ICD-10-CM F40.240
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

F40.240 is a billable ICD-10-CM diagnosis code for claustrophobia. 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
F40.240
Billable Status
Yes — Valid for Submission
Code Describes
Claustrophobia
Short Description
Claustrophobia
Same as the full description in the CMS dataset.
Parent Code
F40.24
Situational type phobia

Code Classification

ChapterF01–F99Mental and behavioural disorders
SectionF40-F48Anxiety, dissociative, stress-related, somatoform and other nonpsychotic mental disorders
CategoryF40Phobic anxiety disorders
This CodeF40.240Claustrophobia

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Claustrophobia
  • Fear of enclosed spaces
  • Fear of phone boxes
  • Fear of tunnels

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.

    • Claustrophobia
    • Phobia, phobic
      • specific (isolated)
        • situational
          • closed in spaces

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

Clinical InformationClinical

  • Claustrophobia

    persistent and irrational fear of enclosed places (e.g., elevators, closets, tunnels) or of being confined (e.g., in an airplane or the backseat of a car). situations where enclosure or confinement may be encountered are often avoided or else endured with intense anxiety or distress. the focus of fear is typically on panic symptoms triggered in these situations, such as feelings of being unable to breathe, choking, sweating, and fears of losing control. (from apa dictionary of psychology, accessed 11/8/2023)

  • Claustrophobia

    an irrational fear of being in a confined space.

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 F40.240 to ICD-9-CMHistory

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

ICD-9-CM
300.29 Isolated/spec phobia NEC
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 F40.240Overview

Is F40.240 (Situational type phobia) a billable code?

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

What is the ICD-9 equivalent of F40.240?

Under the General Equivalence Mappings, claustrophobia converts to ICD-9-CM 300.29 (isolated/spec phobia NEC). 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.