Is F40.21 a billable ICD-10-CM code?

No. F40.21 is a non-billable header code. Code to a higher level of specificity using one of its child codes.

Where does F40.21 sit in the tabular list?

Mental, Behavioral and Neurodevelopmental disorders (F01-F99), in the block Anxiety, dissociative, stress-related, somatoform and other nonpsychotic mental disorders (F40-F48).

F40.21

F40.21 — Animal type phobia

Non-billable headerICD-10-CM

F40.21 is a non-billable header ICD-10-CM code for animal type phobia. It cannot be billed on its own: choose one of the more specific child codes below.

Excludes2 inherited from the categories above F40.21

Also inherited, and the opposite of Excludes1: these conditions are not part of F40.21, but a patient can have both, so you may code both.

Written on F40.2 — Specific (isolated) phobias

dysmorphophobia (nondelusional) (F45.22)
nosophobia (F45.22)

Risk adjustment

F40.21 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Code history

F40.21 has not changed since FY2024 — no addition, revision or deletion across the three most recent ICD-10-CM releases.

Code to one of these instead F40.21

2 child codes. Green means billable.

Related codes at this level

Codes that share F40.2. If F40.21 is not quite right, the correct code is usually one of these.

Questions about F40.21

Is F40.21 a billable ICD-10-CM code?: No. F40.21 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does F40.21 sit in the tabular list?: Mental, Behavioral and Neurodevelopmental disorders (F01-F99), in the block Anxiety, dissociative, stress-related, somatoform and other nonpsychotic mental disorders (F40-F48).