G47.21 Circadian rhythm sleep disorder, delayed sleep phase type

Billable ICD-10-CM code, FY2026.

Applicable to

• Delayed sleep phase syndrome

Applies from G47 Sleep disorders

Excludes2 (not included here)

• nightmares (F51.5)
• nonorganic sleep disorders (F51.-)
• sleep terrors (F51.4)
• sleepwalking (F51.3)

Applies from G47.2 Circadian rhythm sleep disorders

Applicable to

• Disorders of the sleep wake schedule
• Inversion of nyctohemeral rhythm
• Inversion of sleep rhythm

MS-DRG index

Defines the logic of DRG(s) 011-013 in MDC PRE.

Approximate ICD-9-CM (GEMs)

• 327.31 Circadian rhythm sleep disorder, delayed sleep phase type

Code annotations containing back-references to G47.21

Back-references to G47

• Type 2 Excludes: F51 Sleep disorders not due to a substance or known physiological condition ("organic sleep disorders (G47.-)")

Diagnosis Index entries for G47.21

• Delay, delayed › sleep phase syndrome
• Disorder (of) › sleep › circadian rhythm › delayed sleep phase type
• Syndrome › delayed sleep phase

Nearby codes

• G47.13 Recurrent hypersomnia
• G47.14 Hypersomnia due to medical condition
• G47.19 Other hypersomnia
• G47.2 Circadian rhythm sleep disorders
• G47.20 Circadian rhythm sleep disorder, unspecified type
• G47.21 Circadian rhythm sleep disorder, delayed sleep phase type (this code)
• G47.22 Circadian rhythm sleep disorder, advanced sleep phase type
• G47.23 Circadian rhythm sleep disorder, irregular sleep wake type
• G47.24 Circadian rhythm sleep disorder, free running type
• G47.25 Circadian rhythm sleep disorder, jet lag type
• G47.26 Circadian rhythm sleep disorder, shift work type