ICD-10-CM
ICD-10 code for Acid reflux: K21.9
The closest CDC title for "Acid reflux" is K21.9, Gastro-esophageal reflux disease without esophagitis. K21.9 is a billable code.
Source: CDC ICD-10-CM FY2027 order file dated June 16, 2026. Publisher page
Run it in Rivvi
Check every code on your export
Upload a claims or problem-list export. Rivvi flags codes that are not billable, replaced, or unspecified when a specific code exists.
Check my exportFree to start. Opens Rivvi, the AI workspace for healthcare teams.
Codes under K21, then other CDC titles that name gastro-esophageal reflux disease without esophagitis
A header groups codes and is not billed. A billable code is one you can report.
- K21Gastro-esophageal reflux diseaseHeader
- K21.0Gastro-esophageal reflux disease with esophagitisHeader
- K21.00Gastro-esophageal reflux disease with esophagitis, without bleedingBillable
- K21.01Gastro-esophageal reflux disease with esophagitis, with bleedingBillable
- K21.9Gastro-esophageal reflux disease without esophagitisBillable
Excludes1
Excludes1 means these codes are not reported together.
From K21. A note on a category applies to every code under it.
Related conditions
Related pages
- K21.9 code detailsNotes, nearby codes, CMS-HCC group
- Category K21Every code under it
- Chapter 11Diseases of the digestive system
- ICD-10 codes by conditionA to Z
- Check a list of ICD-10 codes
- Denial code CO-11Diagnosis does not support the procedure
- Denial code CO-146Diagnosis invalid for the date of service
- HCPCS Level II code lookup
Questions
What is the ICD-10 code for Acid reflux?
The closest CDC title for "Acid reflux" is K21.9, Gastro-esophageal reflux disease without esophagitis. K21.9 is a billable code.
Is K21.9 billable?
Yes. K21.9 is a billable code in the FY2027 ICD-10-CM file. Use a more specific code when the record documents one.
What documentation notes apply to K21.9?
The CDC tabular list gives 1 Excludes1 note (not coded together) for K21.9 and the categories above it. They are listed on this page.
What chapter is K21.9 in?
Chapter 11. Diseases of the digestive system.
When do ICD-10-CM codes change?
Every October 1, with the new fiscal year file. Some years add April 1 updates. This page uses the FY2027 file, effective October 1, 2026.