K27 ICD-10-CM Code: Peptic ulcer, site unspecified
Billing Status: NO. This is a clinician non-billable / parent hierarchy grouping in the ICD-10-CM system.
Coding at a Glance
- Tabular directives
- 2 inclusion terms · 1 Excludes1 · 1 Excludes2 · 2 use-additional codes
Coding instructions
Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for K27 in the official ICD-10-CM tabular list, quoted as published.
Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2026Effective: October 1, 2025
Notes without a marker are published on K27 itself; “inherited from” names the category or block whose note applies here.
Includes
Conditions the official ICD-10-CM tabular list includes under this code.
- gastroduodenal ulcer NOS
- peptic ulcer NOS
Excludes1 — Not Coded Here
Conditions generally not reported together with this code (Excludes1) -- an error unless the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
- peptic ulcer of newborn (P78.82) Compare K27 vs P78.82 →
Excludes2 — Not Included Here
Conditions not covered by this code, but which may be reported alongside it when both are present.
- hiatus hernia (K44.-) Compare K27 vs K44 →
Source: inherited from K20-K31
Use Additional Code
Supplementary codes the tabular list directs you to add.
- Use additional code to identify:
- alcohol abuse and dependence (F10.-)
Coder workflow for K27
MedCoder structured workflow — derived from this code’s own official record
Before you code K27
- K27 is not reportable as written. Select the more specific code beneath it that the documentation supports. Codes are reported to the highest level of specificity the classification provides (Guidelines I.B.2).
ReviewK27.0, K27.1, K27.2, K27.3, K27.4, K27.5, K27.6, K27.7, K27.9
See the relationships section · Guide: How to choose an ICD-10-CM code →
- Unspecified does not mean incorrect. When the record gives no greater specificity, K27 may be the appropriate code. Check the record for detail that supports a more specific sibling. An unspecified code is for records that do not provide the detail a more specific code needs; a query, not an assumption, is the route to specificity (Guidelines I.A.9.b, I.B.18).
See the relationships section · Guide: Other vs unspecified (NEC vs NOS) →
- Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with K27. Excludes1 conditions are not reported together with this code unless the record shows they are unrelated (Guidelines I.A.12.a).
Choose the right path
- Does the documentation support one of the more specific codes beneath K27?
Yes → Select that code and continue the checks below on its own page.
No → K27 cannot be reported as written; query for the specificity its subcategory needs.ReviewK27.0, K27.1, K27.2, K27.3, K27.4, K27.5, K27.6, K27.7, K27.9
- Does the record document the detail a more specific sibling code needs?
Yes → Review the specific siblings in this subcategory.
No → Continue — K27 is appropriate when the documentation goes no further. - Does the documentation support a condition named in K27’s Excludes1 note?
Yes → Do not simply proceed: review the excluded code. Both are reported only when the record shows the two conditions are unrelated.
No → Continue.ReviewP78.82
Consider K27. Then work the Use Additional Code note, and confirm the code is valid for the date of service in the Verify section.
Documentation check
- The provider’s diagnostic statement
- Codes are assigned from the provider’s documented diagnosis, not from clinical criteria, test values or a medication list (Guidelines I.A.19).
- The conditions the Use Additional Code note names
- Reported with this code when documented; a conditional instruction (“if applicable”, “if known”) applies only when the record supports it.
- Any detail beyond this code’s title
- What the record states that a more specific sibling code would capture — or its absence, which itself supports the unspecified code.
Official instructions as workflow
Excludes1 — check before selecting K27(1 note)
Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with K27: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.
CompareP78.82
See the official tabular notes · Guidelines I.A.12.a
Excludes2 — not part of K27(1 note)
Coding workflow: The conditions named in this note are not included in K27. When the record documents both, both may be reported; the note is a boundary, not a prohibition.
CompareK44
See the official tabular notes · Guidelines I.A.12.b
Use Additional Code — after identifying K27(2 notes)
Coding workflow: Check whether the documentation supports the additional code(s) the note names, and report them with K27 when it does. Where the instruction is conditional (“if applicable”, “if known”), it applies only when the record documents the condition.
ReviewF10
See the official tabular notes · Guidelines I.A.13
Coding decision scenarios
Pattern scenarios for this code’s structure — decision rules, not clinical cases
Documentation: The provider documents the condition in the terms of this code’s title and records no further detail.
Coding question: Is a more specific sibling code supportable?
Path: Review the subcategory for a sibling that names the missing detail.
Reason: A more specific code needs documentation of the distinguishing element; without it the unspecified code is appropriate, and a provider query is the route to specificity (Guidelines I.A.9.b, I.B.18).
Documentation: Both the condition K27 describes and a condition named in its Excludes1 note are documented for the same encounter.
Coding question: Can both codes be reported?
Path: Review the Excludes1 note and the excluded code, and look for a provider statement on whether the two conditions are related.
Reason: Excludes1 means the two are not coded together; the exception is when the record shows the conditions are unrelated to each other (Guidelines I.A.12.a).
ReviewP78.82
Documentation: A condition the Use Additional Code note names is documented.
Coding question: Is a second code reported with K27?
Path: Review the Use Additional Code note and the code it names.
Reason: The additional code is reported when the record documents the condition; a conditional instruction applies only when its condition is met (Guidelines I.A.13).
ReviewF10
Every row is derived from this code’s own record — its title, tabular notes, 7th-character family and same-category siblings — with fixed MedCoder wording; nothing is inferred about a patient. The official notes and guideline text are in the sections each row links to, and they control.
Code Overview
MedCoder summary Summary composed by MedCoder from this code's official ICD-10-CM record. The tabular instructional notes themselves appear verbatim below.
Decision Points
The directives on this code's own record, as a pre-claim checklist.
- 2 Use Additional Code instructions — report the named additional code(s) when the documentation supports them. See the Use Additional Code notes
- 1 Excludes1 entry — codes named there are generally not reported together with this code (Guidelines I.A.12.a). See the Excludes1 notes
- 1 Excludes2 entry — those conditions are not part of this code and may be reported additionally when documented. See the Excludes2 notes
Checklist rows are derived from this code's own official directives; the wording of each check is MedCoder editorial. The official notes themselves are in the sections each row links to.
Verify Before Coding
From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim in Claim Check.
Relationships & Classification
MedCoder structured relationships — computed from published CMS and AHRQ datasets
Other codes that name K27 or its code family, from the CMS ICD-10-CM tabular instructional notes. Tabular-note edges are stored at the code family level that carries each note.
Referenced by 4 Excludes1 notes: K25 — Gastric ulcer, K26 — Duodenal ulcer, K63.3 — Ulcer of intestine, K92.2 — Gastrointestinal hemorrhage, unspecified.
These codes’ tabular lists mark this diagnosis as mutually exclusive — not reported together unless the conditions are documented as unrelated.
Contextual Map
Every relationship of K27 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.
Run K27 with these 7 related codes in Claim Check
Hierarchy
- K00-K95 — Chapter 11: Diseases of the Digestive System (K00-K95) (K00-K95)[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- K20-K31 — Diseases of esophagus, stomach and duodenum[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
Excludes1
- P78.82 — Peptic ulcer of newborn[Excludes1]: “peptic ulcer of newborn (P78.82)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
Excludes2
- K44 — Diaphragmatic hernia[Excludes2]: “hiatus hernia (K44.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
Use Additional Code
- F10 — Alcohol related disorders[Use Additional Code]: “alcohol abuse and dependence (F10.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
Referenced by Excludes1 notes
- K25 — Gastric ulcer[Excludes1]: “peptic ulcer NOS (K27.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
- K26 — Duodenal ulcer[Excludes1]: “peptic ulcer NOS (K27.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
- K63.3 — Ulcer of intestine[Excludes1]: “peptic ulcer, site unspecified (K27.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
- K92.2 — Gastrointestinal hemorrhage, unspecified[Excludes1]: “peptic ulcer with hemorrhage (K25-K28)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
Nearest codes (9)
- K27.0 — Acute peptic ulcer, site unspecified, with hemorrhage[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- K27.1 — Acute peptic ulcer, site unspecified, with perforation[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- K27.2 — Acute peptic ulcer, site unspecified, with both hemorrhage and perforation[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- K27.3 — Acute peptic ulcer, site unspecified, without hemorrhage or perforation[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- K27.4 — Chronic or unspecified peptic ulcer, site unspecified, with hemorrhage[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- K27.5 — Chronic or unspecified peptic ulcer, site unspecified, with perforation[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- K27.6 — Chronic or unspecified peptic ulcer, site unspecified, with both hemorrhage and perforation[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- K27.7 — Chronic peptic ulcer, site unspecified, without hemorrhage or perforation[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- and 1 more
Change history
- FY2016 — In the code set at ICD-10-CM adoption [Change history]— CMS release files (code change ledger) · icd10cm-fy2016
Common coding questions
Can K27 be billed directly?
No. K27 (Peptic ulcer, site unspecified) is a non-billable ICD-10-CM category code. A more specific billable subcode must be selected based on clinical documentation.
Sources for this page
Codes, titles, notes, index terms and mappings on this page are transcribed from the datasets below. Relationships MedCoder computed and text MedCoder wrote are labelled where they appear.
- Code, title, tabular notes and index terms Official source data
- CMS/CDC ICD-10-CM FY2026 tabular list, index and tables, effective October 1, 2025 Release, file and checksum · Publisher’s page
- Claim edits Official source data
- CMS Definitions of Medicare Code Edits — v43.1 (April 2026) Release, file and checksum · Publisher’s page
- Change history and date-of-service validity Official source data
- CMS ICD-10-CM release addenda, ingested release by release into the change ledger Release, file and checksum · Publisher’s page
- Comparisons, relationships and the contextual map MedCoder structured relationship
- Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears
- Summary and FAQ answers MedCoder explanation
- Written by MedCoder to explain the sources above: drafted with AI assistance, checked by a person against the release files, and labelled as MedCoder text where it appears. Not official text.
Labels on this page: Official source data · MedCoder structured relationship · MedCoder explanation. How to read the labels · All data sources and release dates
Cite this page
Reference this page in a research guide, syllabus or article. The release is included because code content changes each year.
MedCoder.ai. "K27 — Peptic ulcer, site unspecified." ICD-10-CM FY2026. https://medcoder.ai/icd10/code/k27-peptic-ulcer-site-unspecified
Change history
- FY2016 — October 1, 2015In the code set at ICD-10-CM adoptionPeptic ulcer, site unspecified
No changes since FY2016 — additions, deletions, description changes and billable-status changes are tracked through FY2027 (effective October 1, 2026), and none are recorded for this code. Note changes are tracked from FY2027 only.
Nearest Codes in This Family
Official ICD-10-CM classifications closest to K27 in its code family, with their registry titles.
- K27.0 — Acute peptic ulcer, site unspecified, with hemorrhage
- K27.1 — Acute peptic ulcer, site unspecified, with perforation
- K27.2 — Acute peptic ulcer, site unspecified, with both hemorrhage and perforation
- K27.3 — Acute peptic ulcer, site unspecified, without hemorrhage or perforation
- K27.4 — Chronic or unspecified peptic ulcer, site unspecified, with hemorrhage
- K27.5 — Chronic or unspecified peptic ulcer, site unspecified, with perforation
- K27.6 — Chronic or unspecified peptic ulcer, site unspecified, with both hemorrhage and perforation
- K27.7 — Chronic peptic ulcer, site unspecified, without hemorrhage or perforation
- K27.9 — Peptic ulcer, site unspecified, unspecified as acute or chronic, without hemorrhage or perforation