Chronic kidney disease (CKD) (N18) ICD-10-CM
The N18 code range covers chronic kidney disease (ckd) with 11 ICD-10-CM diagnosis codes. 9 of them are billable and valid for claim submission in fiscal year 2027, and the category headers group them but cannot themselves be billed.
Code First
Certain conditions have both an underlying etiology and multiple body system manifestations due to the underlying etiology. For such conditions, the ICD-10-CM has a coding convention that requires the underlying condition be sequenced first followed by the manifestation. Wherever such a combination exists, there is a "use additional code" note at the etiology code, and a "code first" note at the manifestation code. These instructional notes indicate the proper sequencing order of the codes, etiology followed by manifestation.
- 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
The “use additional code” indicates that a secondary code could be used to further specify the patient’s condition. This note is not mandatory and is only used if enough information is available to assign an additional code.
Codes in the N18 Range 11 codes · 9 billable
- N18 Chronic kidney disease (CKD)Non-billable
- N18.1 Chronic kidney disease, stage 1
- N18.2 Chronic kidney disease, stage 2 (mild)
- N18.3 Chronic kidney disease, stage 3 (moderate)Non-billable
- N18.30 Chronic kidney disease, stage 3 unspecified
- N18.31 Chronic kidney disease, stage 3a
- N18.32 Chronic kidney disease, stage 3b
- N18.4 Chronic kidney disease, stage 4 (severe)
- N18.5 Chronic kidney disease, stage 5
- N18.6 End stage renal disease
- N18.9 Chronic kidney disease, unspecified
Clinical Terms in This Code Range
Definitions from the National Library of Medicine for conditions coded in the N18 range.
Chronic Kidney Disease
Impairment of the renal function secondary to chronic kidney damage persisting for three or more months.
Chronic Kidney Disease, Stage 1
Long-standing and persistent renal disease with glomerular filtration rate (GFR) greater than 90 ml/min.
Chronic Kidney Disease, Stage 2
Long-standing and persistent renal disease with glomerular filtration rate (GFR) between 60-89 ml/min.
Chronic Kidney Disease, Stage 3
Long-standing and persistent renal disease with glomerular filtration rate (GFR) between 30-59 ml/min.
Chronic Kidney Disease, Stage 3A
Long-standing and persistent renal disease with glomerular filtration rate (GFR) between 45-59 ml/min.
Chronic Kidney Disease, Stage 3B
Long-standing and persistent renal disease with glomerular filtration rate (GFR) between 30-44 ml/min.
Chronic Kidney Disease, Stage 4
Long-standing and persistent renal disease with glomerular filtration rate (GFR) between 15-29 ml/min.
Chronic Kidney Disease, Stage 5
Long-standing and persistent renal disease with glomerular filtration rate (GFR) less than 15 ml/min.
Kidney Failure, Chronic
The end-stage of CHRONIC RENAL INSUFFICIENCY. It is characterized by the severe irreversible kidney damage (as measured by the level of PROTEINURIA) and the reduction in GLOMERULAR FILTRATION RATE to less than 15 ml per min (Kidney Foundation: Kidney Disease Outcome Quality Initiative, 2002). These patients generally require HEMODIALYSIS or KIDNEY TRANSPLANTATION.
About the N18 Code Range
Chronic kidney disease means impaired kidney function caused by lasting kidney damage.
N18 is organized by stage, from N18.1 for stage 1 through N18.5 for stage 5. The titles call stage 2 mild, stage 3 moderate, and stage 4 severe. Stage 3 separates into unspecified stage 3, stage 3a, and stage 3b.
N18.6 identifies end stage renal disease. N18.9 identifies chronic kidney disease without a specified stage.
Questions About This Page
How many billable codes are in the N18 range?
Of the 11 codes in this range, 9 are billable and valid for claim submission from October 1, 2026 through September 30, 2027. Category header codes group them but cannot be reported on claims.
What does the N18 range classify?
The range classifies chronic kidney disease (ckd). Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2027 ICD-10-CM Tabular List and order file, effective October 1, 2026 through September 30, 2027.
