ICD-10-CM 2027
ICD-10 code for walking sleep
From the official ICD-10-CM alphabetic index entry “Sleep › walking”. Page updated September 29, 2026.
About coding walking sleep
The ICD-10-CM code for walking sleep is F51.3 (Sleepwalking [somnambulism]). The official index lists 1 more specific code, so check the documentation for details such as type, cause, site or severity before settling on F51.3.
Within F51 (sleep disorders not due to a substance or known physiological condition), F51.3 is specifically for Sleepwalking [somnambulism]. Related codes cover insomnia not due to a substance or known physiological condition (F51.0), hypersomnia not due to a substance or known physiological condition (F51.1), sleep terrors [night terrors] (F51.4), Nightmare disorder (F51.5), other sleep disorders not due to a substance or known physiological condition (F51.8) and sleep disorder not due to a substance or known physiological condition, unspecified (F51.9).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 887 (Other Mental Disorder Diagnoses, relative weight 1.1139), in MDC 19 (Mental Diseases and Disorders), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
More specific walking sleep codes (official index)
- hysterical F44.89 — Other dissociative and conversion disorders
Common questions about walking sleep ICD-10 codes
What is the ICD-10 code for walking sleep?
- F51.3 — Sleepwalking [somnambulism]. More specific codes apply when the documentation supports them: F44.89.
What is the ICD-10 code for hysterical walking sleep?
- F44.89 — Other dissociative and conversion disorders.
Is F51.3 billable?
- Yes. F51.3 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can F51.3 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict F51.3 as a principal diagnosis.
Is F51.3 a CC or MCC?
- No. F51.3 is neither a CC nor an MCC under MS-DRG v44.0.