2026 ICD-10-CM Diagnosis Code N18.32Chronic kidney disease, stage 3b

ICD-10-CM Codes›N00–N99›N17-N19›CKD

ICD-10-CM N18.32
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

N18.32 is a billable ICD-10-CM diagnosis code for chronic kidney disease, stage 3b. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 8, 19, 682 through 684. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Chronic kidney disease.

For Medicare Advantage risk adjustment, N18.32 maps to CMS-HCC Category 328 (Chronic Kidney Disease, Moderate (Stage 3B)) under the V28 model, adding a risk factor of about 0.127 for a community, non-dual, aged beneficiary in payment year 2026.

Code Identity

ICD-10-CM Code
N18.32
Billable Status
Yes — Valid for Submission
Code Describes
Chronic kidney disease, stage 3b
Short Description
Chronic kidney disease, stage 3b
Same as the full description in the CMS dataset.
Parent Code
N18.3
Chronic kidney disease, stage 3 (moderate)

Code Classification

ChapterN00–N99Diseases of the genitourinary system
SectionN17-N19Acute kidney failure and chronic kidney disease
CategoryCKDChronic kidney disease (N18)
This CodeN18.32Chronic kidney disease, stage 3b

Medicare Risk Adjustment (HCC)Billing

N18.32 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2026.

CMS-HCC V28 Category (Payment Model)
HCC 328— Chronic Kidney Disease, Moderate (Stage 3B)
Payment HCC · PY 2026 one of 1 ICD-10-CM codes in this category
Risk Adjustment Factor (RAF) Weight
+0.127
community, non-dual, aged · ranges 0.116–0.181 across segments
Hierarchy
Superseded by HCC 326 and HCC 327
a more severe related category takes the payment when both are reported
Prior Model (CMS-HCC V24)
HCC 138
V24 retired V28 pays 100% of MA risk scores since PY 2026
Other CMS Models
ESRD (V21): HCC 138 · ESRD (V24): HCC 138
ESRD V21 weights: 0.000 dialysis, 0.000 functioning graft · ESRD V24 weights: 0.000 dialysis, 0.000 functioning graft
Part D (RxHCC)
Not mapped
N18.32 does not risk-adjust in the RxHCC prescription drug model

Source: CMS Payment Year 2026 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Chronic kidney disease stage 3 due to type 1 diabetes mellitus
  • Chronic kidney disease stage 3 due to type 2 diabetes mellitus
  • Chronic kidney disease stage 3B
  • Chronic kidney disease stage 3B due to type 1 diabetes mellitus
  • Chronic kidney disease stage 3B due to type 2 diabetes mellitus
  • Hypertension in chronic kidney disease due to type 1 diabetes mellitus
  • Hypertension in chronic kidney disease due to type 2 diabetes mellitus
  • Hypertension in chronic kidney disease stage 3 due to type 1 diabetes mellitus
  • Hypertension in chronic kidney disease stage 3 due to type 2 diabetes mellitus
  • Hypertension in chronic kidney disease stage 3B due to type 1 diabetes mellitus
  • Hypertension in chronic kidney disease stage 3B due to type 2 diabetes mellitus

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR GEN003
Chronic kidney disease
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Chronic Kidney Disease

You have two kidneys, each about the size of your fist. Their main job is to filter your blood. They remove wastes and extra water, which become urine. They also keep the body's chemicals balanced, help control blood pressure, and make hormones.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Code History & ChangesHistory

Replacement N18.32 replaces the following previously assigned code(s):

  • N18.3 - Chronic kidney disease, stage 3 (moderate)
FY 2021AddedAdded to the ICD-10-CM code setEffective October 1, 2020.
FY 2022–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About N18.32Overview

What is the ICD-10 code for chronic kidney disease, stage 3b?

The ICD-10-CM code for chronic kidney disease, stage 3b is N18.32 (sometimes written as N1832). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

Is N18.32 (Chronic kidney disease, stage 3 (moderate)) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report chronic kidney disease, stage 3b on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does N18.32 group to?

When chronic kidney disease, stage 3b is the principal diagnosis on an inpatient stay, it groups to MS-DRG 8, 19, 682, 683, 684, with relative weights from 0.6003 to 6.6272 depending on complications. Higher weights mean higher Medicare reimbursement.

What HCC is N18.32?

N18.32 (chronic kidney disease, stage 3b) maps to CMS-HCC Category 328 (Chronic Kidney Disease, Moderate (Stage 3B)), commonly written as HCC 328, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2026. It mapped to HCC 138 under the retired V24 model. It also maps in the ESRD (V21) and ESRD (V24) models. It does not map to any RxHCC in the Part D prescription drug model.

Does N18.32 risk-adjust for Medicare Advantage payment?

Yes. When documented and reported on a Medicare Advantage encounter, N18.32 adds a risk adjustment factor of about 0.127 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.116 to 0.181 depending on the payment segment). A more severe related category (HCC 326 and HCC 327) supersedes it when both are reported. See the full factor table on the HCC 328 category page.