2026 ICD-10-CM Diagnosis Code G31Other degenerative diseases of nervous system, not elsewhere classified

ICD-10-CM CodesG00–G99G30-G32G31

ICD-10-CM G31
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

G31 is a non-billable ICD-10-CM category code for other degenerative diseases of nervous system, not elsewhere classified, so it cannot be submitted on claims. Use a more specific code from this category instead, such as G31.01, G31.09, G31.1, and G31.2.

Code Identity

ICD-10-CM Code
G31
Billable Status
No — Non-Billable Category
Code Describes
Other degenerative diseases of nervous system, not elsewhere classified
Chapter
G30-G32
Other degenerative diseases of the nervous system

Code Classification

ChapterG00–G99Diseases of the nervous system
SectionG30-G32Other degenerative diseases of the nervous system
CategoryG31Other degenerative diseases of nervous system, not elsewhere classified
This CodeG31Other degenerative diseases of nervous system, not elsewhere classified

Specific Coding for Oth degenerative diseases of nervous system, NECOverview

Non-specific codes like G31 require more characters. Use one of these billable codes instead:

  • G31.0 for Frontotemporal dementia

  • Use G31.01 for Pick's disease

  • Use G31.09 for Other frontotemporal neurocognitive disorder

  • Use G31.1 for Senile degeneration of brain, not elsewhere classified

  • Use G31.2 for Degeneration of nervous system due to alcohol

  • G31.8 for Other specified degenerative diseases of nervous system

  • Use G31.80 for Leukodystrophy, unspecified

  • Use G31.81 for Alpers disease

  • Use G31.82 for Leigh's disease

  • Use G31.83 for Neurocognitive disorder with Lewy bodies

  • Use G31.84 for Mild cognitive impairment of uncertain or unknown etiology

  • Use G31.85 for Corticobasal degeneration

  • Use G31.86 for Alexander disease

  • Use G31.87 for Primary progressive apraxia of speech

  • Use G31.89 for Other specified degenerative diseases of nervous system

  • Use G31.9 for Degenerative disease of nervous system, unspecified

Tabular List NotesGuidance

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

Use Additional Code

Type 2 Excludes

Patient EducationClinical

Degenerative Nerve Diseases

Degenerative nerve diseases affect many of your body's activities, such as balance, movement, talking, breathing, and heart function. Many of these diseases are genetic. Sometimes the cause is a medical condition such as alcoholism, a tumor, or a stroke. Other causes may include toxins, chemicals, and viruses.

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 G31Overview

Is G31 a billable code?

No. This is a category header that groups the codes for other degenerative diseases of nervous system, not elsewhere classified, and headers cannot be submitted on claims. Claims for other degenerative diseases of nervous system, not elsewhere classified need a more specific code from this category, such as G31.01, G31.09, and G31.1.