2027 ICD-10-CM Diagnosis Code F21Schizotypal disorder

ICD-10-CM Codes›F01–F99›F20-F29›F21

ICD-10-CM F21
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

F21 is a billable ICD-10-CM diagnosis code for schizotypal disorder. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 883. Coders also document this condition as cluster A personality disorder. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Personality disorders and Schizophrenia spectrum and other psychotic disorders.

For Medicare Advantage risk adjustment, F21 maps to CMS-HCC Category 153 (Personality Disorders; Anorexia/Bulimia Nervosa) under the V28 model, adding a risk factor of about 0.396 for a community, non-dual, aged beneficiary in payment year 2027.

Code Identity

ICD-10-CM Code
F21
Billable Status
Yes — Valid for Submission
Code Describes
Schizotypal disorder
Short Description
Schizotypal disorder
Same as the full description in the CMS dataset.
Chapter
F20-F29
Schizophrenia, schizotypal, delusional, and other non-mood psychotic disorders

Code Classification

ChapterF01–F99Mental and behavioural disorders
SectionF20-F29Schizophrenia, schizotypal, delusional, and other non-mood psychotic disorders
CategoryF21Schizotypal disorder
This CodeF21Schizotypal disorder

Medicare Risk Adjustment (HCC)Billing

F21 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2027.

CMS-HCC V28 Category (Payment Model)
HCC 153— Personality Disorders; Anorexia/Bulimia Nervosa
Payment HCC · PY 2027 one of 35 ICD-10-CM codes in this category
Risk Adjustment Factor (RAF) Weight
+0.396
community, non-dual, aged · ranges 0.199–0.464 across segments
Hierarchy
Superseded by HCC 151 and HCC 152
a more severe related category takes the payment when both are reported
Prior Model (CMS-HCC V24)
HCC 60
V24 retired V28 pays 100% of MA risk scores since PY 2026
Other CMS Models
ESRD (V24): HCC 60
ESRD V24 weights: 0.066 dialysis, 0.000–0.225 functioning graft
Part D (RxHCC)
RxHCC 133 — Anxiety and Other Psychiatric Disorders
also risk-adjusts in the Part D prescription drug model (V08)

Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Cluster A personality disorder
  • Schizophrenic prodrome
  • Schizotypal personality disorder

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to F21: its own notes plus those printed at Chapter 5. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

From Chapter 5 (F01-F99) Mental and behavioural disorders applies to 872 codes
  • disorders of psychological development

Applicable To

Conditions this code is used for: synonyms of the title or, for "other specified" codes, the conditions assigned to it. The list is not exhaustive.

  • Borderline schizophrenia
  • Latent schizophrenia
  • Latent schizophrenic reaction
  • Prepsychotic schizophrenia
  • Prodromal schizophrenia
  • Pseudoneurotic schizophrenia
  • Pseudopsychopathic schizophrenia
  • Schizotypal personality disorder

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

On F21 itself
  • Asperger's syndrome (F84.5)
  • schizoid personality disorder (F60.1)
From Chapter 5 (F01-F99) Mental and behavioural disorders applies to 872 codes
  • symptoms, signs and abnormal clinical laboratory findings, not elsewhere classified (R00-R99)

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name F21, its category, or a range that includes it.

Excludes1 3

These codes carry an Excludes1 note naming F21: they are not reported together with it, unless the two conditions are unrelated.

  • F53 Mental and behavioral disorders associated with the puerperium, not elsewhere classified
    psychosis in schizophrenia, schizotypal, delusional, and other psychotic disorders (F20-F29) names F20-F29, which includes this code
  • R44 Other symptoms and signs involving general sensations and perceptions
    hallucinations in schizophrenia, schizotypal and delusional disorders (F20-F29) names F20-F29, which includes this code
  • R46 Symptoms and signs involving appearance and behavior
    appearance and behavior in schizophrenia, schizotypal and delusional disorders (F20-F29) names F20-F29, which includes this code

Excludes2 2

These codes carry an Excludes2 note naming F21: its condition is not part of those codes, and both may be reported when the patient has both.

  • F20 Schizophrenia
    schizotypal disorder (F21)
  • F60.1 Schizoid personality disorder
    schizotypal disorder (F21)

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Clinical ClassificationClinical

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

CCSR MBD009
Personality disorders
Default principal diagnosis: inpatient No · outpatient No
CCSR MBD001
Schizophrenia spectrum and other psychotic disorders
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Schizotypal Personality Disorder

    a disorder characterized by an enduring pattern of inability to establish close relationships coupled with cognitive or perceptual distortions, odd beliefs and speech, and eccentric behavior and appearance.

Patient EducationClinical

Personality Disorders

Your personality is your own way of thinking, feeling, behaving, and relating to others. Once you become an adult, your personality usually doesn't change much.

The full article covers:

  • What is personality?
  • What are personality disorders?
  • What are the types of personality disorders?
  • What causes personality disorders?
  • What are the symptoms of personality disorders?
  • How are personality disorders diagnosed?
  • How are personality disorders treated?

Read the full article at MedlinePlus

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

Convert F21 to ICD-9-CMHistory

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

ICD-9-CM
301.22 Schizotypal person dis
Exact Match The mapping is direct, with no qualifiers.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About F21Overview

What is the ICD-10 code for schizotypal disorder?

The ICD-10-CM code for schizotypal disorder is F21. It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is F21 (Schizotypal disorder) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report schizotypal disorder on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does F21 group to?

When schizotypal disorder is the principal diagnosis on an inpatient stay, it groups to MS-DRG 883 (disorders of Personality and Impulse Control), which carries a relative weight of 1.7398. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of F21?

Under the General Equivalence Mappings, schizotypal disorder converts to ICD-9-CM 301.22 (schizotypal person dis). The mapping is a direct match.

What HCC is F21?

F21 (schizotypal disorder) maps to CMS-HCC Category 153 (Personality Disorders; Anorexia/Bulimia Nervosa), commonly written as HCC 153, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It mapped to HCC 60 under the retired V24 model. It also maps in the ESRD (V24) model. In the Part D prescription drug model it maps to RxHCC 133.

Does F21 risk-adjust for Medicare Advantage payment?

Yes. When documented and reported on a Medicare Advantage encounter, F21 adds a risk adjustment factor of about 0.396 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.199 to 0.464 depending on the payment segment). A more severe related category (HCC 151 and HCC 152) supersedes it when both are reported. See the full factor table on the HCC 153 category page.