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ICD-10-CM tabular list

W20-W49Exposure to inanimate mechanical forces

ICD-10-CM codes W20-W49 cover exposure to inanimate mechanical forces, within external causes of morbidity. The block holds 728 codes across 26 categories, of which 510 are billable and 218 are header codes that cannot be submitted on a claim. 728 of them (100%) require a 7th character.

Excludes1 — never code together

These conditions cannot occur together. Billing both on the same encounter is a denial.

  • assault (X92-Y09)
  • contact or collision with animals or persons (W50-W64)
  • exposure to inanimate mechanical forces involving military or war operations (Y36.-, Y37.-)
  • intentional self-harm (X71-X83)

The 7th character in W20-W49

A code in this block is not complete without its 7th character, and a missing one is a rejected claim rather than a denied one: the clearinghouse never passes it on. 728 of the 728 codes here take one.

A
initial encounter
D
subsequent encounter
S
sequela

What else to watch in W20-W49

  • 66 codes are named in Medicare coverage policies. An LCD or NCD lists them as supporting medical necessity, or explicitly as not supporting it. Which applies depends on the MAC for your state.

Categories in W20-W49

ICD-10-CMFY2026-Apr· effective April 1, 2026