Is N18 a billable ICD-10-CM code?

No. N18 is a non-billable header code. Code to a higher level of specificity using one of its child codes.

Where does N18 sit in the tabular list?

Diseases of the genitourinary system (N00-N99), in the block Acute kidney failure and chronic kidney disease (N17-N19).

N18

N18 — Chronic kidney disease (CKD)

Non-billable headerICD-10-CM

N18 is a non-billable header ICD-10-CM code for chronic kidney disease (ckd). It cannot be billed on its own: choose one of the more specific child codes below.

Code first

The underlying condition must be sequenced before this code.

any associated:
diabetic chronic kidney disease (E08.22, E09.22, E10.22, E11.22, E13.22)
hypertensive chronic kidney disease (I12.-, I13.-)

Use additional code

Add a secondary code to capture the detail described below.

code, if applicable, to identify:
associated cachexia (E88.A)
kidney transplant status (Z94.0)

Other codes that can never be billed with N18

These codes carry an Excludes1 note pointing at N18. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading N18 alone.

N18.5Chronic kidney disease, stage 5
N19Unspecified kidney failure
N28.9Disorder of kidney and ureter, unspecified

Risk adjustment

N18 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 N18

7 child codes. Green means billable.

Questions about N18

Is N18 a billable ICD-10-CM code?: No. N18 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does N18 sit in the tabular list?: Diseases of the genitourinary system (N00-N99), in the block Acute kidney failure and chronic kidney disease (N17-N19).