Is Z91 a billable ICD-10-CM code?

No. Z91 is a non-billable header code. Code to a higher level of specificity using one of its child codes.

Where does Z91 sit in the tabular list?

Factors influencing health status and contact with health services (Z00-Z99), in the block Persons with potential health hazards related to family and personal history and certain conditions influencing health status (Z77-Z99).

Z91

Z91 — Personal risk factors, not elsewhere classified

Non-billable headerICD-10-CM

Z91 is a non-billable header ICD-10-CM code for personal risk factors, not elsewhere classified. It cannot be billed on its own: choose one of the more specific child codes below.

Excludes2 — not included here, but may coexist

The excluded condition is not part of this code, but a patient can have both. You may code both.

contact with and (suspected) exposures hazardous to health (Z77.-)
exposure to pollution and other problems related to physical environment (Z77.1-)
female genital mutilation status (N90.81-)
occupational exposure to risk factors (Z57.-)
personal history of physical injury and trauma (Z87.81, Z87.82-)

Other codes that can never be billed with Z91

These codes carry an Excludes1 note pointing at Z91. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading Z91 alone.

Z91.0111Allergy to milk products with tolerance to baked milk
Z91.0112Allergy to milk products with reactivity to baked milk
Z91.0121Allergy to eggs with tolerance to baked egg
Z91.0122Allergy to eggs with reactivity to baked egg

Risk adjustment

Z91 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 Z91

7 child codes. Green means billable.

Questions about Z91

Is Z91 a billable ICD-10-CM code?: No. Z91 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does Z91 sit in the tabular list?: Factors influencing health status and contact with health services (Z00-Z99), in the block Persons with potential health hazards related to family and personal history and certain conditions influencing health status (Z77-Z99).