Non-Billable / Non-Specific Code
ICD-10-CM K21 is the diagnosis code for Gastro-esophageal reflux disease. This code falls under the section "Diseases of esophagus, stomach and duodenum" within Chapter 11 — Diseases of the digestive system (K00-K95). It is a non-billable/non-specific ICD-10-CM code that should not be used for reimbursement. A more specific sub-code is required for billing. Medical coders and healthcare providers use this code to document and classify diagnoses in electronic health records, insurance claims, and clinical databases.
The following conditions should never be coded at the same time as K21. They are mutually exclusive:
Understanding where K21 sits in the ICD-10-CM classification helps ensure proper coding:
No, K21 is a non-billable/non-specific code. You should use a more specific sub-code for billing and reimbursement.
K21 is the ICD-10-CM diagnosis code for "Gastro-esophageal reflux disease". It is used by healthcare providers to classify and document this condition in medical records and insurance claims.
K21 is located in Section K20-K31 — "Diseases of esophagus, stomach and duodenum" within Chapter 11 of the ICD-10-CM Tabular List.
K21 has 2 sub-code(s) that provide more specific detail: K21.0, K21.9.
Use K21 when the patients documented diagnosis matches "Gastro-esophageal reflux disease" and the clinical documentation supports this level of specificity. Always verify with the latest ICD-10-CM guidelines and payer requirements.
The ICD-10-CM code for Gastro-esophageal reflux disease is K21.
No, K21 is non-billable. Use a more specific sub-code for primary diagnosis billing.
K21 is in Chapter 11 of the ICD-10-CM Tabular List.
Type 1 Excludes for K21 include: newborn esophageal reflux (P78.83).
Yes, K21 is a valid ICD-10-CM code for the 2026 fiscal year, subject to official CMS updates.