What is ICD-10 code F40.00?

F40.00 is the ICD-10-CM diagnosis code for Agoraphobia, unspecified. An anxiety disorder where a person has intense fear and avoidance of open or crowded spaces, public transportation, or situations where escape might be difficult. It belongs to the ICD-10-CM chapter for mental, behavioral and neurodevelopmental disorders (f01-f99). F40.00 is a billable code, meaning it can be reported on a claim as a primary or secondary diagnosis when supported by documentation. F40.00 is part of the FY2026 ICD-10-CM code set published by the CMS National Center for Health Statistics and used on Medicare, Medicaid, and commercial claims in the United States.

Yes. F40.00 is a billable ICD-10-CM code that can be reported on professional and institutional claims as a primary or secondary diagnosis when the provider documentation supports the specific condition described. Billable codes in ICD-10-CM are coded to the highest level of specificity available for the documented diagnosis. F40.00 is current for fiscal year 2026 and remains in the active CMS ICD-10-CM code set published by the National Center for Health Statistics.

What is the V28 vs V24 difference for F40.00?

F40.00 does not map to a payment HCC under either the CMS-HCC V28 risk adjustment model or the older V24 model. V28 reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition. Because neither model rewards F40.00 with a risk adjustment factor, it contributes zero to a Medicare Advantage beneficiary's RAF score in either version. Coders should check whether provider documentation supports a more specific child code that does map to a payment HCC.

What should coders know when reporting F40.00?

Agoraphobia can occur with or without panic disorder; F40.00 is used when panic disorder is not present Document whether the agoraphobia is mild, moderate, or severe for clinical clarity

F40.00: Agoraphobia, unspecified — ICD-10

ICD-10-CM Code View

HCC Buddy Code Card

Digital ICD-10 code-book layout with official code detail, always-visible risk models, Code Trumping, and Buddy coding guidance.

Code lookupF40.00Effective periodFY2026 Apr Update (Apr 1-Sep 30)

FY 2026 Apr update / Mental, Behavioral and Neurodevelopmental disorders (F01-F99) / Anxiety, dissociative, stress-related, somatoform and other nonpsychotic mental disorders (F40-F48)

F40.00

Billable / SpecificICD-10-CMOfficial ICD-10-CMCodebook guidance

Agoraphobia, unspecified

An anxiety disorder where a person has intense fear and avoidance of open or crowded spaces, public transportation, or situations where escape might be difficult.

Buddy Insight

Agoraphobia, unspecified, describes a marked fear or avoidance of situations where escape might be difficult, such as open spaces, crowds, or being outside the home alone.

CMS-HCC V28

Not risk-adjusted for this model/period.

RAF 0

CMS-HCC V24

Not risk-adjusted for this model/period.

RAF 0

ACA/HHS

Not risk-adjusted for this model/period.

RAF 0

ESRD/PACE

Not risk-adjusted for this model/period.

RAF 0

RXHCC

Mapped

HCC 133

Personality Disorders, Anxiet...

RAF 0.0

Code Trumping

Basket needed

Compare selected patient codes to show trumped or trumps impact.

Code Book Path

Official

F40Phobic anxiety disorders

F40.0Agoraphobia

F40.00Agoraphobia, unspecified

Inclusion Terms

Official

ICD-10-CM does not list inclusion terms for F40.00 in this effective period.

Excludes 2

Official

ICD-10-CM does not list Excludes 2 notes for F40.00 in this effective period.

Related Child Codes

Official

F40.01Agoraphobia with panic disorder

F40.02Agoraphobia without panic disorder

Includes

Official

ICD-10-CM does not list Includes notes for F40.00 in this effective period.

Excludes 1

Official

ICD-10-CM does not list Excludes 1 notes for F40.00 in this effective period.

Code First

Official

ICD-10-CM does not list Code First sequencing instructions for F40.00 in this effective period.

Use Additional

Official

ICD-10-CM does not list Use Additional Code instructions for F40.00 in this effective period.

Code Also

Official

ICD-10-CM does not list Code Also instructions for F40.00 in this effective period.

Buddy Documentation Tip

HCC Buddy guidance

Marked fear or anxiety about two or more agoraphobic situations (public transportation, open spaces, enclosed places, standing in line/crowds, being outside the home alone)

Duration of symptoms (typically 6+ months)

Avoidance behaviors and their impact on daily functioning

Distinction from panic disorder (document whether panic attacks are present or absent)

MEAT Support

HCC Buddy guidance

Marked fear or anxiety about two or more agoraphobic situations (public transportation, open spaces, enclosed places, standing in line/crowds, being outside the home alone)

Duration of symptoms (typically 6+ months)

Avoidance behaviors and their impact on daily functioning

Distinction from panic disorder (document whether panic attacks are present or absent)

Audit Caution

HCC Buddy guidance

Using the unspecified code F40.00 when documentation specifies whether panic disorder is present or absent — use F40.01 or F40.02 instead

Confusing agoraphobia with social phobia — agoraphobia is about escape difficulty, not social evaluation

Coding agoraphobia when the patient simply prefers to stay home without meeting clinical criteria for the disorder

Failing to query the provider about panic disorder comorbidity to achieve greater code specificity

Common Mistakes

HCC Buddy guidance

F40.01 (Agoraphobia with panic disorder) — Use F40.01 when panic attacks occur in agoraphobic situations; F40.00 does not specify panic disorder presence

F40.02 (Agoraphobia without panic disorder) — Use F40.02 when documentation explicitly states no panic disorder; F40.00 is for unspecified cases

F41.0 (Panic disorder) — Panic disorder can exist without agoraphobia; distinguish based on whether situational avoidance is the primary feature

F40.10 (Social phobia, unspecified) — Social phobia involves fear of social evaluation; agoraphobia involves fear of situations where escape is difficult

Last updated: FY2026 ICD-10-CM Apr update, Apr 1, 2026 through Sep 30, 2026. CMS-HCC V28 is 100% phased in for payment year 2026.

Is F40.00 an HCC code?

No. F40.00 is a billable ICD-10-CM code but does not map to any HCC category in V28, V24, ESRD, or RxHCC.

HCC Category Mapping

RxHCCHCC 133, Personality Disorders, Anxiety, and Other Specified Mental Disorders

0.000

RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.

MEAT Criteria for F40.00

For F40.00to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically, it has to be re-documented and supported each calendar year.

MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
EEvaluate: test results, medication response, or physical findings reviewed by the provider
AAssess: explicit mention in the assessment or plan with acknowledgment of status
TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis

Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed F40.00 during that encounter, not just copy-forwarded from a problem list.

Coder workflow notes

Get the V28 RAF + MEAT cheat sheet

One printable page: confirm a code's V28 HCC status, its RAF weight, and the MEAT your note needs to make it stick. Free, no card.

Free PDF. No card. Unsubscribe anytime.

What This Code Means

F40.00 is the ICD-10-CM diagnosis code for agoraphobia, unspecified. An anxiety disorder where a person has intense fear and avoidance of open or crowded spaces, public transportation, or situations where escape might be difficult. F40.00 sits in the ICD-10-CM chapter for mental, behavioral and neurodevelopmental disorders (f01-f99), within the section covering anxiety, dissociative, stress-related, somatoform and other nonpsychotic mental disorders (f40-f48).

F40.00 is a billable ICD-10-CM code but does not map to a payment HCC under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can be reported on Medicare Advantage encounter data submissions but it does not contribute to a beneficiary's RAF score and therefore does not affect risk-adjusted payments to the plan.

F40.00 does not map to any HCC under either V24 or V28 CMS-HCC models and carries no RAF weight for Medicare Advantage risk adjustment. It also has no ESRD HCC mapping. Under RxHCC, it maps to RxHCC 133 at 0.0 weight. This is a non-risk-adjusting code, but accurate documentation remains important for clinical care coordination and medication management.

HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for F40.00 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

•Agoraphobia can occur with or without panic disorder; F40.00 is used when panic disorder is not present
•Document whether the agoraphobia is mild, moderate, or severe for clinical clarity

Clinical Significance

Agoraphobia, unspecified, describes a marked fear or avoidance of situations where escape might be difficult, such as open spaces, crowds, or being outside the home alone. This condition can be severely disabling, limiting patients' ability to access healthcare. It does not map to any HCC under V24 or V28, making it a non-risk-adjusting diagnosis, though it remains clinically important for care management.

Documentation Requirements

✓Marked fear or anxiety about two or more agoraphobic situations (public transportation, open spaces, enclosed places, standing in line/crowds, being outside the home alone)
✓Duration of symptoms (typically 6+ months)
✓Avoidance behaviors and their impact on daily functioning
✓Distinction from panic disorder (document whether panic attacks are present or absent)
✓Differential diagnosis ruling out social anxiety, specific phobias, or other anxiety disorders
✓Current treatment plan including cognitive-behavioral therapy and/or pharmacotherapy

Commonly Confused Codes

•F40.01 (Agoraphobia with panic disorder): Use F40.01 when panic attacks occur in agoraphobic situations; F40.00 does not specify panic disorder presence
•F40.02 (Agoraphobia without panic disorder): Use F40.02 when documentation explicitly states no panic disorder; F40.00 is for unspecified cases
•F41.0 (Panic disorder): Panic disorder can exist without agoraphobia; distinguish based on whether situational avoidance is the primary feature
•F40.10 (Social phobia, unspecified): Social phobia involves fear of social evaluation; agoraphobia involves fear of situations where escape is difficult