2026 ICD-10-CM Diagnosis Code M04Autoinflammatory syndromes

ICD-10-CM Codes›M00–M99›M04›M04

ICD-10-CM M04
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

M04 is a non-billable ICD-10-CM category code for autoinflammatory syndromes, so it cannot be submitted on claims. Use a more specific code from this category instead, such as M04.1, M04.2, M04.8, and M04.9.

Code Identity

ICD-10-CM Code
M04
Billable Status
No — Non-Billable Category
Code Describes
Autoinflammatory syndromes
Short Description
Autoinflammatory syndromes
Same as the full description in the CMS dataset.
Chapter
M04
Autoinflammatory syndromes

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM04Autoinflammatory syndromes
CategoryM04Autoinflammatory syndromes
This CodeM04Autoinflammatory syndromes

Specific Coding for Autoinflammatory syndromesOverview

Non-specific codes like M04 require more characters. Use one of these billable codes instead:

  • Use M04.1 for Periodic fever syndromes

  • Use M04.2 for Cryopyrin-associated periodic syndromes

  • Use M04.8 for Other autoinflammatory syndromes

  • Use M04.9 for Autoinflammatory syndrome, unspecified

Tabular List NotesGuidance

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

Type 2 Excludes

  • Crohn's disease K50

Patient EducationClinical

Autoimmune Diseases

Your immune system protects you from disease and infection by attacking germs that get into your body, such as viruses and bacteria. Your immune system can tell that the germs aren't part of you, so it destroys them. If you have an autoimmune disease, your immune system attacks the healthy cells of your organs and tissues by mistake.

The full article covers:

  • What are autoimmune diseases?
  • What causes autoimmune diseases?
  • Who is at risk for autoimmune diseases?
  • What are the symptoms of autoimmune diseases?
  • How are autoimmune diseases diagnosed?
  • What are the treatments for autoimmune diseases?

Read the full article at MedlinePlus

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

Code HistoryHistory

FY 2018AddedAdded to the ICD-10-CM code setEffective October 1, 2017.
FY 2019–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About M04Overview

Is M04 (Autoinflammatory syndromes) a billable code?

No. This is a category header that groups the codes for autoinflammatory syndromes, and headers cannot be submitted on claims. Claims for autoinflammatory syndromes need a more specific code from this category, such as M04.1, M04.2, and M04.8.