ICD-11 Codes for Mental, Behavioral, and Neurodevelopmental Disorders
Chapter 6 of the ICD-11 covers mental, behavioral, and neurodevelopmental disorders. This page provides a complete list of the four-character diagnostic categories in the chapter, organized by block according to the WHO classification. Where there is a clear match, the tables also show the corresponding ICD-10 code.
How to Read ICD-11 Codes
ICD-11 codes in Chapter 6 begin with the number 6. The characters that follow identify the diagnostic block and category. For example, 6A20 is the code for schizophrenia, while 6A70 is the code for single episode depressive disorder. In ICD-10, these disorders were generally identified by codes beginning with the letter F, such as F20 for schizophrenia and F32 for depressive disorders.
Additional characters after the decimal point provide more specific information about a diagnosis, such as its severity, course, or clinical presentation. A final Y indicates an “other specified” category, while Z indicates an “unspecified” category. The individual subcodes are explained in more detail on the pages linked from the tables.
The ICD-10 column lists the closest corresponding ICD-10 code when there is a clear equivalent. The two classification systems do not always map directly onto each other. Some ICD-11 diagnoses combine categories that were previously separate, while others divide an ICD-10 category into several distinct diagnoses. ICD-11 also introduced diagnoses that did not have a direct equivalent in ICD-10, including complex post-traumatic stress disorder and gaming disorder. When there is no clear ICD-10 equivalent, the table shows a dash (–).
Other specified secondary mental or behavioural syndrome
–
6E6Z
Secondary mental or behavioural syndrome, unspecified
–
Other chapter 6 categories
ICD-11 code
Title
Closest ICD-10 equivalent
6E40
Psychological or behavioural factors affecting disorders or diseases classified elsewhere
–
Frequently Asked Questions
Which ICD-11 chapter covers mental disorders?
Mental, behavioral, and neurodevelopmental disorders are covered in Chapter 6 of the ICD-11. It takes the place of Chapter V in the ICD-10, which used codes F00–F99. Some conditions that were included in the mental disorders chapter in ICD-10 are now classified elsewhere in ICD-11. For example, sleep-wake disorders are covered in Chapter 7, while sexual dysfunctions and gender incongruence are included in Chapter 17.
Can an ICD-11 code be converted to an ICD-10 code?
Not always. There is no one-to-one correspondence between the two classification systems for every diagnosis. The WHO provides mapping tables to help identify possible equivalents, but a single ICD-11 diagnosis may correspond to several ICD-10 codes, while some newer ICD-11 diagnoses have no direct ICD-10 equivalent.
For that reason, mapping between ICD-11 and ICD-10 should not be treated as a simple code-for-code conversion. The appropriate code may depend on the clinical context and requires professional judgment.
Where can I find the official ICD-11 classification?
The official ICD-11 is available through the WHO’s ICD-11 Browser at icd.who.int. The WHO also provides a coding tool and mapping tables for working with the classification.
This page is intended as a convenient reference and should not be used in place of the official WHO classification.
Source: WHO ICD-11 MMS, Chapter 6. ICD-11 is made available by the WHO under the CC BY-ND 3.0 IGO license. ICD Diagnostica is not affiliated with or endorsed by the WHO.
Author: Patryk Malejka, M.A. in Psychology (clinical specialisation) · Source: WHO ICD-11 MMS · Last updated: 15 September 2026
