2026 ICD-10-CM Diagnosis Code N03Chronic nephritic syndrome

ICD-10-CM Codes›N00–N99›N00-N08›N03

ICD-10-CM N03
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

N03 is a non-billable ICD-10-CM category code for chronic nephritic syndrome, so it cannot be submitted on claims. Use a more specific code from this category instead, such as N03.0, N03.1, N03.2, and N03.3.

Code Identity

ICD-10-CM Code
N03
Billable Status
No — Non-Billable Category
Code Describes
Chronic nephritic syndrome
Chapter
N00-N08
Glomerular diseases

Code Classification

ChapterN00–N99Diseases of the genitourinary system
SectionN00-N08Glomerular diseases
CategoryN03Chronic nephritic syndrome
This CodeN03Chronic nephritic syndrome

Specific Coding for Chronic nephritic syndromeOverview

Non-specific codes like N03 require more characters. Use one of these billable codes instead:

  • Use N03.0 for Chronic nephritic syndrome with minor glomerular abnormality

  • Use N03.1 for Chronic nephritic syndrome with focal and segmental glomerular lesions

  • Use N03.2 for Chronic nephritic syndrome with diffuse membranous glomerulonephritis

  • Use N03.3 for Chronic nephritic syndrome with diffuse mesangial proliferative glomerulonephritis

  • Use N03.4 for Chronic nephritic syndrome with diffuse endocapillary proliferative glomerulonephritis

  • Use N03.5 for Chronic nephritic syndrome with diffuse mesangiocapillary glomerulonephritis

  • Use N03.6 for Chronic nephritic syndrome with dense deposit disease

  • Use N03.7 for Chronic nephritic syndrome with diffuse crescentic glomerulonephritis

  • Use N03.8 for Chronic nephritic syndrome with other morphologic changes

  • Use N03.9 for Chronic nephritic syndrome with unspecified morphologic changes

  • Use N03.A for Chronic nephritic syndrome with C3 glomerulonephritis

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Includes

  • chronic glomerular disease
  • chronic glomerulonephritis
  • chronic nephritis

Type 1 Excludes

  • chronic tubulo-interstitial nephritis N11
  • diffuse sclerosing glomerulonephritis N05.8
  • nephritic syndrome NOS N05

Patient EducationClinical

Kidney Diseases

You have two kidneys, each about the size of your fist. They are near the middle of your back, just below the rib cage. Inside each kidney there are about a million tiny structures called nephrons. They filter your blood. They remove wastes and extra water, which become urine. The urine flows through tubes called ureters.

Read the full article at MedlinePlus

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

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About N03Overview

Is N03 (Chronic nephritic syndrome) a billable code?

No. This is a category header that groups the codes for chronic nephritic syndrome, and headers cannot be submitted on claims. Claims for chronic nephritic syndrome need a more specific code from this category, such as N03.0, N03.1, and N03.2.