What is ICD-10 code F40.241?

F40.241 is the ICD-10-CM diagnosis code for Acrophobia. An intense, irrational fear of heights that can cause anxiety or panic when at significant elevations. It belongs to the ICD-10-CM chapter for mental, behavioral and neurodevelopmental disorders (f01-f99). F40.241 is a billable code, meaning it can be reported on a claim as a primary or secondary diagnosis when supported by documentation. F40.241 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. F40.241 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. F40.241 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 F40.241?

F40.241 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 F40.241 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 F40.241?

Note the severity and functional impact (e.g., inability to use stairs, visit tall buildings) Verify this is a phobic disorder rather than normal caution about heights

F40.241: Acrophobia — 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 lookupF40.241Effective 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)

F40.241

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

Acrophobia

An intense, irrational fear of heights that can cause anxiety or panic when at significant elevations.

Buddy Insight

Acrophobia is a specific phobia involving intense fear of heights.

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

F40.2Specific (isolated) phobias

F40.24Situational type phobia

F40.241Acrophobia

Inclusion Terms

Official

ICD-10-CM does not list inclusion terms for F40.241 in this effective period.

Excludes 2

Official

ICD-10-CM does not list Excludes 2 notes for F40.241 in this effective period.

Related Child Codes

Official

F40.240Claustrophobia

F40.242Fear of bridges

F40.243Fear of flying

F40.248Other situational type phobia

Includes

Official

ICD-10-CM does not list Includes notes for F40.241 in this effective period.

Excludes 1

Official

ICD-10-CM does not list Excludes 1 notes for F40.241 in this effective period.

Code First

Official

ICD-10-CM does not list Code First sequencing instructions for F40.241 in this effective period.

Use Additional

Official

ICD-10-CM does not list Use Additional Code instructions for F40.241 in this effective period.

Code Also

Official

ICD-10-CM does not list Code Also instructions for F40.241 in this effective period.

Buddy Documentation Tip

HCC Buddy guidance

Marked fear or anxiety specifically about heights

Disproportionate fear relative to actual danger in the height-related situation

Consistent anxiety response when encountering heights

Avoidance behaviors and functional impact (occupational, social, daily activities)

MEAT Support

HCC Buddy guidance

Marked fear or anxiety specifically about heights

Disproportionate fear relative to actual danger in the height-related situation

Consistent anxiety response when encountering heights

Avoidance behaviors and functional impact (occupational, social, daily activities)

Audit Caution

HCC Buddy guidance

Using F40.248 or F40.228 when acrophobia has its own specific code

Confusing acrophobia with vertigo (R42) — vertigo is a vestibular symptom, acrophobia is a psychiatric condition

Coding acrophobia for reasonable fear responses in genuinely dangerous height situations

Not capturing acrophobia when it is the underlying reason for occupational limitations

Common Mistakes

HCC Buddy guidance

F40.248 (Other situational type phobia) — Use the specific acrophobia code F40.241 rather than the general situational category

F40.228 (Other natural environment type phobia) — Acrophobia is classified as situational, not natural environment, in ICD-10-CM

F40.240 (Claustrophobia) — Both are situational phobias but involve different stimuli; they can coexist

R42 (Dizziness and giddiness) — Vertigo symptoms at heights should be distinguished from height phobia

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 F40.241 an HCC code?

No. F40.241 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 F40.241

For F40.241to 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 F40.241 during that encounter, not just copy-forwarded from a problem list.

What This Code Means

F40.241 is the ICD-10-CM diagnosis code for acrophobia. An intense, irrational fear of heights that can cause anxiety or panic when at significant elevations. F40.241 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).

F40.241 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.

F40.241 does not map to any HCC under V24 or V28. No ESRD mapping. RxHCC maps to RxHCC 133 at 0.0 weight. Non-risk-adjusting diagnosis. Coders reviewing F40.241 should check whether additional documentation would support a more specific child code in the same hierarchy that does map to a payment HCC, capturing the correct specificity is the highest-impact RAF improvement available within accurate coding.

HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for F40.241 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

•Note the severity and functional impact (e.g., inability to use stairs, visit tall buildings)
•Verify this is a phobic disorder rather than normal caution about heights

Clinical Significance

Acrophobia is a specific phobia involving intense fear of heights. It is one of the most common specific phobias and can range from fear of extreme heights to inability to climb stairs or use escalators. The phobia can significantly impact daily functioning and occupational capacity, particularly for individuals whose work involves elevated positions.

Documentation Requirements

✓Marked fear or anxiety specifically about heights
✓Disproportionate fear relative to actual danger in the height-related situation
✓Consistent anxiety response when encountering heights
✓Avoidance behaviors and functional impact (occupational, social, daily activities)
✓Duration of 6+ months
✓Current treatment if applicable

Commonly Confused Codes

•F40.248 (Other situational type phobia): Use the specific acrophobia code F40.241 rather than the general situational category
•F40.228 (Other natural environment type phobia): Acrophobia is classified as situational, not natural environment, in ICD-10-CM
•F40.240 (Claustrophobia): Both are situational phobias but involve different stimuli; they can coexist
•R42 (Dizziness and giddiness): Vertigo symptoms at heights should be distinguished from height phobia