ICD-10-CM 2027 diagnosis code
R12Heartburn
R12 is a valid, billable ICD-10-CM code for heartburn. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.
Looking up by condition? See ICD-10 code for Brash, ICD-10 code for Pyrosis, ICD-10 code for Waterbrash.
Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data
About R12
R12 is the ICD-10-CM diagnosis code for Heartburn. It belongs to block R10-R19 (symptoms and signs involving the digestive system and abdomen) and chapter 18 (symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.
Don't report R12 together with the conditions in its Excludes1 note: functional dyspepsia (K30).
The conditions in its Excludes2 note aren't part of R12, but may be coded alongside it if the patient has both: dyspepsia NOS (R10.13).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 391 (Esophagitis, Gastroenteritis and Miscellaneous Digestive Disorders with MCC, relative weight 1.2392) and DRG 392 (Esophagitis, Gastroenteritis and Miscellaneous Digestive Disorders without MCC, relative weight 0.7645), in MDC 06 (Diseases and Disorders of the Digestive System), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.
Before ICD-10, this condition was coded in ICD-9-CM as 787.1 (Heartburn).
Coding notes
Notes that apply from higher levels
Instructions written at a parent level also apply to R12.
Broader instructions also apply from R10-R19 Symptoms and signs involving the digestive system and abdomen and Chapter 18: Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified.
Alphabetic index entries
4 entriesTerms in the official ICD-10-CM index that lead to R12.
Codes whose notes reference R12
- K30Excludes1
MS-DRG v44.0 grouping
All DRGs →Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.
MDC 06 · Diseases and Disorders of the Digestive System
ICD-9-CM equivalent
Converter →- 787.1Heartburnexact
From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
- No changes since FY2016.
Common questions about R12
Is R12 billable?
- Yes. R12 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can R12 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict R12 as a principal diagnosis.
Is R12 a CC or MCC?
- No. R12 is neither a CC nor an MCC under MS-DRG v44.0.
What DRG does R12 group to?
- R12 is used in the MS-DRG v44.0 logic for MS-DRG 391 (Esophagitis, Gastroenteritis and Miscellaneous Digestive Disorders with MCC) and MS-DRG 392 (Esophagitis, Gastroenteritis and Miscellaneous Digestive Disorders without MCC). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.
What is the ICD-9 code for R12?
- The CMS General Equivalence Mappings map R12 to ICD-9-CM 787.1.