K21 — Gastro-esophageal reflux disease
Is K21 billable?
No — K21 is a non-billable header code. K21 groups more specific codes and cannot be submitted on a claim. A valid ICD-10-CM code must be reported at the highest level of specificity available in its branch. Select one of the 3 billable codes beneath K21.
K21 at a glance
| Code | K21 |
|---|---|
| Description | Gastro-esophageal reflux disease |
| Billable | No — header code |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
Excludes1 — never code together
The conditions below can never be reported together with K21 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
- newborn esophageal reflux (P78.83)
Excludes2 — not included here — inherited from Chapter 11
The conditions below are not part of K21, but a patient may have both at the same time. When documentation supports it, K21 and the excluded code may both be reported.
- certain conditions originating in the perinatal period (P04-P96)
- certain infectious and parasitic diseases (A00-B99)
- complications of pregnancy, childbirth and the puerperium (O00-O9A)
- congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
- endocrine, nutritional and metabolic diseases (E00-E88)
- injury, poisoning and certain other consequences of external causes (S00-T88)
- neoplasms (C00-D49)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
Excludes2 — not included here — inherited from K20-K31
The conditions below are not part of K21, but a patient may have both at the same time. When documentation supports it, K21 and the excluded code may both be reported.
- hiatus hernia (K44.-)
What codes fall under K21? (2)
How long has K21 existed?
K21 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.