R99
R99: Ill-defined and unknown cause of mortality
Billable / specific codeICD-10-CM
R99 is a billable, specific ICD-10-CM code for ill-defined and unknown cause of mortality. It is valid for submission on a claim.
Check R99 with the rest of the claim: free scrubberInclusion terms
Alternative wordings a physician may use in the chart for this same code.
- Death (unexplained) NOS
- Unspecified cause of mortality
Risk adjustment
No CMS-HCC V28 category: this code does not change a RAF score.
Alphabetic index entries that lead here
- Cot death
- Crib death
- Death(cause unknown) (of) (unexplained) (unspecified cause)
- Sudden infant death syndrome(SIDS)
- Syndrome›crib death
Code history
Unchanged in every release from FY2024 to FY2027.