ICD-10-CM Tabular Index · Chapter 11 · FY 2027 K20–K31
Diseases of esophagus, stomach and duodenum (K20-K31) ICD-10-CM
The K20–K31 section covers diseases of esophagus, stomach and duodenum with 136 ICD-10-CM diagnosis codes, of which 106 are billable in fiscal year 2027. The section is organized into the 11 code ranges listed below.
✓ Built from the official CMS FY 2027 datasetEffective Oct 1, 2026 – Sep 30, 2027
11
Code Ranges
136
Diagnosis Codes
106
Billable Codes
K20–K31
Code Range
Type 2 Excludes
A type 2 excludes note represents "Not included here". An excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.
The info icon previews the code ranges inside each row and its instructional notations from the official Tabular List.
About the K20–K31 Code Range
These conditions affect the esophagus, stomach, or duodenum. They include reflux, ulcers, inflammation, and other disorders of those sites.
The esophagus categories separate inflammation of the esophagus, called esophagitis (K20), from reflux (K21). Reflux means stomach contents flow back into the esophagus; its codes distinguish whether esophagitis is present. K22 lists other esophageal diseases, while K23 names esophageal disorders in diseases classified elsewhere.
The ulcer categories distinguish ulcers of the stomach (K25), duodenum (K26), and gastrojejunal site (K28). K27 applies when the peptic ulcer site is unspecified. Their subdivisions separate acute from chronic or unspecified ulcers and distinguish bleeding, perforation, both, or neither.
K29 groups gastritis and duodenitis, with gastritis subdivisions that include acute, alcoholic, and chronic forms. K30 names functional dyspepsia, or impaired digestion, especially after eating. K31 lists other stomach and duodenal diseases.
FY 2027 changes: The FY 2027 ICD-10-CM update, effective October 1, 2026, added K31.B.
Questions About This Page
How many codes are in the K20-K31 range?
The K20-K31 range contains 136 ICD-10-CM diagnosis codes in FY 2027. 106 of them are billable, and the rest are category headers that organize the section.
What conditions does K20-K31 cover?
The range covers diseases of esophagus, stomach and duodenum. The code ranges listed above break it into groups of related conditions, and each one links to its own page with the full code list.
The “use additional code” indicates that a secondary code could be used to further specify the patient’s condition. This note is not mandatory and is only used if enough information is available to assign an additional code.
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
A type 2 excludes note represents "Not included here". An excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
A type 2 excludes note represents "Not included here". An excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.
Certain conditions have both an underlying etiology and multiple body system manifestations due to the underlying etiology. For such conditions, the ICD-10-CM has a coding convention that requires the underlying condition be sequenced first followed by the manifestation. Wherever such a combination exists, there is a "use additional code" note at the etiology code, and a "code first" note at the manifestation code. These instructional notes indicate the proper sequencing order of the codes, etiology followed by manifestation.
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
This note appears immediately under a three character code title to further define, or give examples of, the content of the category.
erosion (acute) of stomach
pylorus ulcer (peptic)
stomach ulcer (peptic)
Use Additional Code
The “use additional code” indicates that a secondary code could be used to further specify the patient’s condition. This note is not mandatory and is only used if enough information is available to assign an additional code.
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
This note appears immediately under a three character code title to further define, or give examples of, the content of the category.
erosion (acute) of duodenum
duodenum ulcer (peptic)
postpyloric ulcer (peptic)
Use Additional Code
The “use additional code” indicates that a secondary code could be used to further specify the patient’s condition. This note is not mandatory and is only used if enough information is available to assign an additional code.
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
This note appears immediately under a three character code title to further define, or give examples of, the content of the category.
gastroduodenal ulcer NOS
peptic ulcer NOS
Use Additional Code
The “use additional code” indicates that a secondary code could be used to further specify the patient’s condition. This note is not mandatory and is only used if enough information is available to assign an additional code.
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
This note appears immediately under a three character code title to further define, or give examples of, the content of the category.
anastomotic ulcer (peptic) or erosion
gastrocolic ulcer (peptic) or erosion
gastrointestinal ulcer (peptic) or erosion
gastrojejunal ulcer (peptic) or erosion
jejunal ulcer (peptic) or erosion
marginal ulcer (peptic) or erosion
stomal ulcer (peptic) or erosion
Use Additional Code
The “use additional code” indicates that a secondary code could be used to further specify the patient’s condition. This note is not mandatory and is only used if enough information is available to assign an additional code.
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
Indigestion
Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
This note appears immediately under a three character code title to further define, or give examples of, the content of the category.
functional disorders of stomach
Type 2 Excludes
A type 2 excludes note represents "Not included here". An excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.
