ICD-10-CM Code K21.9
Gastro-esophageal reflux disease without esophagitis
Diagnosis information
Billable
Yes
Valid for claim submission
Chapter
K00–K95
Diseases of the digestive system
Risk adjustment
None
Not risk-adjustable (V28)
Procedures commonly billed with K21.9
CPT/HCPCS procedures frequently paired with K21.9 on claims. The diagnosis helps support medical necessity for the service, but documentation, the service performed, and payer/CMS policy all apply — link each line item to the diagnosis that best documents why it was needed.
- 99214Office/outpatient visit, established patient, moderate complexity
More codes in the K21 category
Other billable ICD-10-CM codes in the same category as K21.9. Coding to the highest specificity the documentation supports is what keeps a claim clean — pick the child code that most precisely matches the diagnosis.
Documentation & coding notes
- K21.9 is a billable/specific ICD-10-CM code — it can be reported as a primary or secondary diagnosis when the documentation supports it. Code to the highest level of specificity the record allows.
- Always verify the code against the current ICD-10-CM Official Guidelines and the payer's coverage policy before submitting — coverage, medical necessity edits, and sequencing rules vary by payer.
Related K00–K95 codes
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Medical coding disclaimer
ICD-10-CM codes and descriptions shown are from the CMS FY2026 official code set and HCC mappings from the CMS-HCC V28 model (payment year 2026), shown for educational reference. Official Guidelines, payer coverage, medical-necessity edits, and sequencing rules vary. Always verify with the current ICD-10-CM Official Guidelines and the payer before submitting claims. D3rx is not responsible for coding or billing outcomes.