2026 ICD-10-CM Diagnosis Code Q26Congenital malformations of great veins

ICD-10-CM Codes›Q00-Q99›Q20-Q28›Q26

ICD-10-CM Q26
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

Q26 is a non-billable ICD-10-CM category code for congenital malformations of great veins, so it cannot be submitted on claims. Use a more specific code from this category instead, such as Q26.0, Q26.1, Q26.2, and Q26.3.

Code Identity

ICD-10-CM Code
Q26
Billable Status
No — Non-Billable Category
Code Describes
Congenital malformations of great veins
Chapter
Q20-Q28
Congenital malformations of the circulatory system

Code Classification

ChapterQ00-Q99Congenital malformations, deformations and chromosomal abnormalities
SectionQ20-Q28Congenital malformations of the circulatory system
CategoryQ26Congenital malformations of great veins
This CodeQ26Congenital malformations of great veins

Specific Coding for Congenital malformations of great veinsOverview

Non-specific codes like Q26 require more characters. Use one of these billable codes instead:

  • Use Q26.0 for Congenital stenosis of vena cava

  • Use Q26.1 for Persistent left superior vena cava

  • Use Q26.2 for Total anomalous pulmonary venous connection

  • Use Q26.3 for Partial anomalous pulmonary venous connection

  • Use Q26.4 for Anomalous pulmonary venous connection, unspecified

  • Use Q26.5 for Anomalous portal venous connection

  • Use Q26.6 for Portal vein-hepatic artery fistula

  • Use Q26.8 for Other congenital malformations of great veins

  • Use Q26.9 for Congenital malformation of great vein, unspecified

Patient EducationClinical

Congenital Heart Defects

Congenital heart defects (CHDs) are problems with the structure of the heart. "Congenital" means that that the problems are present at birth. These defects happen when a fetus's heart doesn't develop normally during pregnancy. Congenital heart defects are the most common type of birth defect.

The full article covers:

  • What are congenital heart defects?
  • What causes congenital heart defects?
  • Who is more likely to have a baby with a congenital heart defect?
  • What are the symptoms of congenital heart defects?
  • What other problems do congenital heart defects cause?
  • How are congenital heart defects diagnosed?
  • What are the treatments for congenital heart defects?

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 Q26Overview

Is Q26 (Congenital malformations of great veins) a billable code?

No. This is a category header that groups the codes for congenital malformations of great veins, and headers cannot be submitted on claims. Claims for congenital malformations of great veins need a more specific code from this category, such as Q26.0, Q26.1, and Q26.2.