K26 vs K27
K26 (Duodenal ulcer) compared with K27 (Peptic ulcer, site unspecified), from the official CMS tabular data. Do not report these codes together: the official tabular list marks them Excludes1.
Can these codes be reported together?
No — do not report together. K26 carries an Excludes1 note covering K27: “peptic ulcer NOS (K27.-)”
Sole exception: when the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
Side by side
| K26Duodenal ulcer | K27Peptic ulcer, site unspecified | |
|---|---|---|
| Billing status | Non-billable header | Non-billable header |
| Classification | K00-K95 — Diseases of the Digestive System (K00-K95) | K00-K95 — Diseases of the Digestive System (K00-K95) |
| Definition | Duodenal ulcer is a non-billable ICD-10-CM category code (K26). | Peptic ulcer, site unspecified is a non-billable ICD-10-CM category code (K27). |
| Includes | erosion (acute) of duodenum duodenum ulcer (peptic) postpyloric ulcer (peptic) | gastroduodenal ulcer NOS peptic ulcer NOS |
| Use additional code | code to identify: alcohol abuse and dependence (F10.-) | code to identify: alcohol abuse and dependence (F10.-) |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources