Mental Health ICD-10 Codes: Quick Reference
Codes verified against the CMS FY2027 ICD-10-CM code descriptions (effective October 1, 2026; these codes are unchanged from FY2026). Reviewed . See sources.
What are mental health ICD-10 codes?
Mental health diagnoses are coded in Chapter 5 of ICD-10-CM (F01 to F99), with social and family factors in the Z codes. A billable code has every required character: F41.1 is billable, but the category F41 is not. This reference lists common codes with their official FY2027 descriptions and links to detailed guides.
ICD-10-CM is the diagnosis code set used on US claims. It is updated every October 1, and FY2027 took effect October 1, 2026. None of the mental health codes on this page changed from FY2026 to FY2027; the only Chapter 5 addition in FY2027 was F64.A, gender identity disorder, in remission.
Each code below shows the official description and whether it is billable. The diagnosis is the treating clinician's decision, and the code follows the documentation. For the service side of a claim, see the CPT code reference.
Common mental health ICD-10-CM codes
| Code | Official description (FY2027) | Billable | When it fits |
|---|---|---|---|
| F41.1 | Generalized anxiety disorder | Yes | Anxiety codes guide |
| F41.9 | Anxiety disorder, unspecified | Yes | Anxiety codes guide |
| F41.0 | Panic disorder [episodic paroxysmal anxiety] | Yes | Anxiety codes guide |
| F32.A | Depression, unspecified | Yes | Depression codes guide |
| F32.9 | Major depressive disorder, single episode, unspecified | Yes | Depression codes guide |
| F33.1 | Major depressive disorder, recurrent, moderate | Yes | Depression codes guide |
| F90.0 | Attention-deficit hyperactivity disorder, predominantly inattentive type | Yes | ADHD codes guide |
| F90.2 | Attention-deficit hyperactivity disorder, combined type | Yes | ADHD codes guide |
| F43.10 | Post-traumatic stress disorder, unspecified | Yes | PTSD codes guide |
| F43.23 | Adjustment disorder with mixed anxiety and depressed mood | Yes | Adjustment disorder guide |
| F31.81 | Bipolar II disorder | Yes | Bipolar codes guide |
| F31.9 | Bipolar disorder, unspecified | Yes | Bipolar codes guide |
| Z63.0 | Problems in relationship with spouse or partner | Yes | Secondary only. Z codes guide |
ICD-10 code guides by condition
- ICD-10 Codes for Anxiety: F41.1, F41.9 and Related CodesICD-10 codes for anxiety: F41.1 generalized anxiety disorder, F41.9 unspecified, F41.0 panic disorder, and related codes, with billable status and note tips.
- ICD-10 Codes for Depression: F32 and F33ICD-10 codes for depression and major depressive disorder: F32.9, F32.A, F33.1 and every F32/F33 code, with billable status, severity rules, and note tips.
- ICD-10 Codes for ADHD: F90.0, F90.1, F90.2ADHD ICD-10 codes: F90.0 inattentive, F90.1 hyperactive, F90.2 combined, F90.8 and F90.9, with billable status, Excludes notes, and session note tips.
- ICD-10 Codes for PTSD: F43.10, F43.11, F43.12PTSD ICD-10 codes: F43.10 unspecified, F43.11 acute, F43.12 chronic, plus acute stress reaction and related trauma codes, with billable status and note tips.
- Z Codes for Mental Health: List and When to Use ThemZ codes for mental health: social determinants (Z55 to Z65), relationship, counseling, and history codes, with billable status and when Z codes can be primary.
- ICD-10 Codes for Adjustment Disorder: F43.20 to F43.29Adjustment disorder ICD-10 codes F43.20 to F43.29, including F43.23 mixed anxiety and depressed mood, with billable status, Excludes rules, and note tips.
- ICD-10 Codes for Bipolar Disorder: F31Bipolar disorder ICD-10 codes in F31: current episode, remission, bipolar II (F31.81) and unspecified (F31.9), with billable status and session note tips.
Psychosis and schizophrenia codes
Psychotic disorders are coded in F20 to F29. F29 has the inclusion term "Psychosis NOS" and is the code when the record says psychosis without a more specific diagnosis. Category F20 has an Excludes1 note for brief psychotic disorder (F23), schizoaffective disorder (F25.-) and mood disorders with psychotic symptoms, so those are coded in their own categories.
| Code | Official description (FY2027) | Billable | When it fits |
|---|---|---|---|
| F29 | Unspecified psychosis not due to a substance or known physiological condition | Yes | Inclusion term: Psychosis NOS. |
| F23 | Brief psychotic disorder | Yes | Documented brief psychotic disorder. |
| F22 | Delusional disorders | Yes | Documented delusional disorder. |
| F20.0 | Paranoid schizophrenia | Yes | Documented paranoid schizophrenia. |
| F20.81 | Schizophreniform disorder | Yes | Documented schizophreniform disorder. |
| F20.9 | Schizophrenia, unspecified | Yes | Schizophrenia without type specified. |
| F25.0 | Schizoaffective disorder, bipolar type | Yes | F25.1 is depressive type; F25.9 unspecified. |
Insomnia codes: F51 or G47?
ICD-10-CM splits insomnia between two chapters. F51.0 codes cover insomnia not due to a substance or known physiological condition. G47.0 codes, in the nervous system chapter, cover insomnia due to a medical condition and "insomnia NOS": subcategory F51.0 has an Excludes2 note sending insomnia NOS, organic insomnia and insomnia due to a known physiological condition to G47.0-. F51.05, insomnia due to other mental disorder, carries a "code also" note for the associated mental disorder.
| Code | Official description (FY2027) | Billable | When it fits |
|---|---|---|---|
| F51.01 | Primary insomnia | Yes | Inclusion term: idiopathic insomnia. |
| F51.02 | Adjustment insomnia | Yes | Insomnia linked to a stressor. |
| F51.04 | Psychophysiologic insomnia | Yes | Documented psychophysiologic insomnia. |
| F51.05 | Insomnia due to other mental disorder | Yes | Code also the associated mental disorder. |
| F51.09 | Other insomnia not due to a substance or known physiological condition | Yes | Other specified nonorganic insomnia. |
| G47.00 | Insomnia, unspecified | Yes | Insomnia NOS. |
Alcohol and substance use disorder codes
Substance-related codes run from F10 (alcohol) to F19. Each has use, abuse and dependence subcategories. When the record mentions more than one pattern for the same substance, the FY2027 guidelines (Section I.C.5.b.2) say to assign one code using a hierarchy: abuse over use, and dependence over abuse or use. The guidelines also say mild substance use disorders in early or sustained remission go to the abuse in remission codes, and moderate or severe ones to the dependence in remission codes. Remission codes are assigned only from the provider's documentation.
| Code | Official description (FY2027) | Billable | When it fits |
|---|---|---|---|
| F10.10 | Alcohol abuse, uncomplicated | Yes | Alcohol abuse. |
| F10.11 | Alcohol abuse, in remission | Yes | Mild alcohol use disorder in remission maps here. |
| F10.20 | Alcohol dependence, uncomplicated | Yes | Alcohol dependence. |
| F10.21 | Alcohol dependence, in remission | Yes | Moderate or severe alcohol use disorder in remission maps here. |
| F12.10 | Cannabis abuse, uncomplicated | Yes | Cannabis abuse. |
| F12.20 | Cannabis dependence, uncomplicated | Yes | Cannabis dependence. |
| F11.20 | Opioid dependence, uncomplicated | Yes | Opioid dependence. |
Other frequently used mental health codes
| Code | Official description (FY2027) | Billable | When it fits |
|---|---|---|---|
| F42.2 | Mixed obsessional thoughts and acts | Yes | Obsessive-compulsive disorder. |
| F40.10 | Social phobia, unspecified | Yes | Social anxiety. |
| F34.1 | Dysthymic disorder | Yes | Persistent depressive disorder documented as dysthymia. |
| F43.81 | Prolonged grief disorder | Yes | Inclusion term: complicated grief. |
| F60.3 | Borderline personality disorder | Yes | Documented borderline personality disorder. |
| F84.0 | Autistic disorder | Yes | Inclusion term: autism spectrum disorder. |
| F91.3 | Oppositional defiant disorder | Yes | Documented ODD. |
| F50.2 | Bulimia nervosa | No (header) | Heading. Use F50.20 to F50.25. |
| F99 | Mental disorder, not otherwise specified | Yes | Use only when nothing more specific is documented. |
What makes an ICD-10 code billable?
A code is billable (valid on a claim) only when it is carried to the full number of characters the code set requires. Section IV.F.2 of the FY2027 Official Guidelines says a three-character code is used only if it is not further subdivided, and a code is invalid if it lacks required characters. That is why F41 and F43.1 are headings while F41.1 and F43.10 are billable.
The guidelines also say to code to the highest level of specificity supported by the record (Section IV.F.3), and, in outpatient care, not to code diagnoses written as probable, suspected or rule out (Section IV.H). Code the symptoms instead until a diagnosis is confirmed.
What should the session note show?
- Write the diagnosis in words in the assessment, and make sure it matches the code on the claim.
- Record the specifiers the code depends on: episode, severity, remission, presentation, or subtype.
- Show current symptoms and functional impact each session, not only at intake.
- Note social and family factors in plain language so Z codes can be supported.
- Use a consistent format such as SOAP, DAP or BIRP so reviewers can find the assessment quickly.
Common mistakes
- Billing a category heading (F41, F43.1, F31.7) instead of a complete code.
- Coding "rule out" diagnoses on outpatient claims.
- Listing a social determinant Z code (Z55 to Z65) first.
- Keeping an unspecified code after the clinician has documented a specific diagnosis.
- Using a code from an outdated code set. FY2027 took effect October 1, 2026.
Frequently Asked Questions
What ICD-10 code set is current?
FY2027 ICD-10-CM, effective October 1, 2026 through September 30, 2027. The codes on this page are unchanged from FY2026.
What is the ICD-10 code for psychosis?
F29, Unspecified psychosis not due to a substance or known physiological condition. Its inclusion term is Psychosis NOS. Specific psychotic disorders have their own codes, such as F23 for brief psychotic disorder and F20.9 for schizophrenia, unspecified.
What is the ICD-10 code for insomnia?
It depends on the cause. F51.01 is primary insomnia and F51.05 is insomnia due to other mental disorder. G47.00 is insomnia, unspecified, which is where insomnia NOS is coded.
What is the ICD-10 code for alcohol use disorder?
ICD-10-CM codes alcohol use by pattern: F10.10 alcohol abuse, uncomplicated, and F10.20 alcohol dependence, uncomplicated, are the most common. The guidelines map mild disorders in remission to F10.11 and moderate or severe disorders in remission to F10.21.
What is the ICD-10 code for schizophrenia?
F20.9 is schizophrenia, unspecified. Specific types include F20.0 paranoid schizophrenia and F20.81 schizophreniform disorder.
Does WellNotes assign diagnosis codes?
No. WellNotes drafts session notes in formats such as SOAP, DAP, and BIRP from your session input. The clinician chooses and documents the diagnosis and codes.
Related references
Sources
- CMS: FY2027 ICD-10-CM code descriptions in tabular order (zip)
- CMS: FY2027 ICD-10-CM code tables, tabular and index (zip)
- CMS and NCHS: ICD-10-CM Official Guidelines for Coding and Reporting, FY2027 (PDF)
- CMS: ICD-10 code files (FY2027 and FY2026 ICD-10-CM)
- CDC NCHS: ICD-10-CM and the ICD-10-CM Browser Tool
Payer rules vary. Confirm diagnosis, coverage, modifier, and documentation rules with each payer before billing. This page is general education, not billing, coding, or legal advice. The diagnosis is the treating clinician's decision.
Draft the session note in SOAP, DAP, or BIRP
WellNotes drafts your session note from what you type or dictate. You choose the diagnosis and codes, and you review every note before it is used.