K21: Gastro-esophageal reflux disease
Codes under K21 (Gastro-esophageal reflux disease). A ✓ marks a billable (fully specified) code; category codes without a ✓ are not billable on their own.
| Code | Description | Billable |
|---|---|---|
| K21.0 | Gastro-esophageal reflux disease with esophagitis | — |
| K21.0 | Gastro-esophageal reflux disease with esophagitis | — |
| K21.00 | Gastro-esophageal reflux disease with esophagitis, without bleeding | ✓ |
| K21.00 | Gastro-esophageal reflux disease with esophagitis, without bleeding | ✓ |
| K21.01 | Gastro-esophageal reflux disease with esophagitis, with bleeding | ✓ |
| K21.01 | Gastro-esophageal reflux disease with esophagitis, with bleeding | ✓ |
| K21.9 | Gastro-esophageal reflux disease without esophagitis | ✓ |
| K21.9 | Gastro-esophageal reflux disease without esophagitis | ✓ |
Frequently asked questions
What is ICD-10-CM code K21?
K21 is an ICD-10-CM category covering Gastro-esophageal reflux disease. It contains 8 more specific diagnosis codes, 6 of which are billable.
Is K21 a billable code?
No — K21 is a category header and isn't billable on its own. Code to the highest level of specificity using one of its subcodes (for example K21.0 — Gastro-esophageal reflux disease with esophagitis). 6 of the 8 codes under K21 are billable.
What codes fall under K21?
K21 includes K21.0, K21.0, K21.00, K21.00, K21.01, plus 3 more. See the full list with descriptions and billable status above.
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Informational only, not coding or medical advice. Verify against the official ICD-10-CM (FY2026) and your payer's guidelines.
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