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ICD-10-CM 2027

ICD-10 code for Crib death

R99

Ill-defined and unknown cause of mortality

✓ Billable / specific

From the official ICD-10-CM alphabetic index entry “Crib death”. Page updated September 29, 2026.

About coding Crib death

The ICD-10-CM code for Crib death is R99 (Ill-defined and unknown cause of mortality).

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 951 (Other Factors Influencing Health Status, relative weight 0.5577), in MDC 23 (Factors Influencing Health Status and Other Contacts with Health Services), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Common questions about Crib death ICD-10 codes

What is the ICD-10 code for Crib death?

R99 — Ill-defined and unknown cause of mortality.

Is R99 billable?

Yes. R99 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).

Can R99 be used as a principal diagnosis?

Yes. The Medicare Code Editor doesn't restrict R99 as a principal diagnosis.

Is R99 a CC or MCC?

No. R99 is neither a CC nor an MCC under MS-DRG v44.0.