W20 vs W31
W20 (Struck by thrown, projected or falling object) compared with W31 (Contact with other and unspecified machinery), 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. W20 carries an Excludes1 note covering W31: “falling object in machinery accident (W24, W28-W31)”
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
| W20Struck by thrown, projected or falling object | W31Contact with other and unspecified machinery | |
|---|---|---|
| Billing status | Non-billable header Report instead: W20.0XXA, W20.0XXD, W20.0XXS, W20.1XXA, W20.1XXD | Non-billable header Report instead: W31.0XXA, W31.0XXD, W31.0XXS, W31.1XXA, W31.1XXD |
| Classification | V00-Y99 — External Causes of Morbidity (V00-Y99) | V00-Y99 — External Causes of Morbidity (V00-Y99) |
| Definition | Struck by thrown, projected or falling object is a non-billable ICD-10-CM category code (W20). | Contact with other and unspecified machinery is a non-billable ICD-10-CM category code (W31). |
| 7th character | The appropriate 7th character is to be added to each code from category W20 | The appropriate 7th character is to be added to each code from category W31 |
| Code first | any associated: cataclysm (X34-X39) | — |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources