New ICD-10 Code Added to Recognize Those Who Died Suddenly

ICD-10 is the 10th revision of the International Statistical Classification of Diseases and Related Health Problems, a medical classification list by the World Health Organization.

Ill-defined and unknown cause of mortality 2016 2017 2018 2019 2020 2021 2022 2023 Billable/Specific Code 

R99 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes. 

The 2023 edition of ICD-10-CM R99 became effective on October 1, 2022. 

This is the American ICD-10-CM version of R99 - other international versions of ICD-10 R99 may differ. 

Applicable To 

Death (unexplained) NOS 

Unspecified cause of mortality 

The following code(s) above R99 contain annotation back-references that may be applicable to R99: R00-R99 Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified Approximate Synonyms 

Death in less than 24 hours from onset of symptoms 

Death less than 24 hr from onset of symptoms 

Instantaneous death 

Sudden infant death syndrome 

Unattended death