2027 ICD-10-CM Diagnosis Code N03Chronic nephritic syndrome

ICD-10-CM Codes›N00–N99›N00-N08›N03

ICD-10-CM N03
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

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
Short Description
Chronic nephritic syndrome
Same as the full description in the CMS dataset.
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

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to N03: its own notes plus those printed at block N00-N08 and Chapter 14. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

  • chronic glomerular disease
  • chronic glomerulonephritis
  • chronic nephritis

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

On N03 itself
  • chronic tubulo-interstitial nephritis (N11.-)
  • diffuse sclerosing glomerulonephritis (N05.8-)
  • nephritic syndrome NOS (N05.-)
From Block N00-N08 Glomerular diseases applies to 107 codes
  • hypertensive chronic kidney disease (I12.-)

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From Chapter 14 (N00-N99) Diseases of the genitourinary system applies to 838 codes
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)

Code Also

A second code may be needed to fully describe the condition; the note gives no sequencing direction.

From Block N00-N08 Glomerular diseases applies to 107 codes
  • any associated kidney failure (N17-N19).

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

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 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About N03Overview

What is the ICD-10 code for chronic nephritic syndrome?

N03 is the ICD-10-CM category for chronic nephritic syndrome, but it is a non-billable header: claims need a more specific code from this category, listed on this page.

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.

Can N03 be reported with a code from N11?

Not as a rule. The Excludes1 note on N03 lists "chronic tubulo-interstitial nephritis (N11.-)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).