K21Header code — not billable

Gastro-esophageal reflux disease

Chapter
11. Diseases of the digestive system
Category
K21
Effective date
October 1, 2026

Related codes in category K21

K21.0Gastro-esophageal reflux disease with esophagitisK21.00Gastro-esophageal reflux dis with esophagitis, without bleedYesK21.01Gastro-esophageal reflux dis with esophagitis, with bleedYesK21.9Gastro-esophageal reflux disease without esophagitisYes

Frequently asked questions

What is ICD-10 code K21?

K21 is an ICD-10-CM diagnosis code for Gastro-esophageal reflux disease.

Is K21 a billable code?

No. K21 is a category/header code, not billable on its own — use one of its more specific child codes instead.

What ICD-10-CM chapter is K21 in?

K21 falls under Chapter 11: Diseases of the digestive system.

When did K21 become effective?

K21 has been effective since October 1, 2026, per the CMS/CDC ICD-10-CM annual release.

What other codes are related to K21?

K21 belongs to category K21, which includes 4 other codes — see the related codes list on this page.

ICD-10-CM data maintained by CDC/CMS (public domain). Always verify codes with authoritative sources before making coding or billing decisions.