Is A00 a billable ICD-10-CM code?

No. A00 is a non-billable header code. Code to a higher level of specificity using one of its child codes.

Where does A00 sit in the tabular list?

Certain infectious and parasitic diseases (A00-B99), in the block Intestinal infectious diseases (A00-A09).

A00

A00 — Cholera

Non-billable headerICD-10-CM

A00 is a non-billable header ICD-10-CM code for cholera. It cannot be billed on its own: choose one of the more specific child codes below.

Other codes that can never be billed with A00

These codes carry an Excludes1 note pointing at A00. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading A00 alone.

T88.7Unspecified adverse effect of drug or medicament
T88.7XXAUnspecified adverse effect of drug or medicament, initial encounter
T88.7XXDUnspecified adverse effect of drug or medicament, subsequent encounter
T88.7XXSUnspecified adverse effect of drug or medicament, sequela

Risk adjustment

A00 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 A00

3 child codes. Green means billable.

Questions about A00

Is A00 a billable ICD-10-CM code?: No. A00 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does A00 sit in the tabular list?: Certain infectious and parasitic diseases (A00-B99), in the block Intestinal infectious diseases (A00-A09).