Y99
Y99 — External cause status
Non-billable headerICD-10-CM
Y99 is a non-billable header ICD-10-CM code for external cause status. It cannot be billed on its own: choose one of the more specific child codes below.
Notes
Additional guidance from the ICD-10-CM tabular list.
- A single code from category Y99 should be used in conjunction with the external cause code(s) assigned to a record to indicate the status of the person at the time the event occurred.
Other codes that can never be billed with Y99
These codes carry an Excludes1 note pointing at Y99. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading Y99 alone.
Risk adjustment
Y99 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.
Code to one of these instead Y99
5 child codes. Green means billable.
Questions about Y99
- Is Y99 a billable ICD-10-CM code?
- No. Y99 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
- Where does Y99 sit in the tabular list?
- External causes of morbidity (V00-Y99), in the block Supplementary factors related to causes of morbidity classified elsewhere (Y90-Y99).