2027 ICD-10-CM Diagnosis Code W55Contact with other mammals

ICD-10-CM Codes›V01–Y99›W50-W64›W55

ICD-10-CM W55
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

W55 is a non-billable ICD-10-CM category code for contact with other mammals, so it cannot be submitted on claims. Use a more specific code from this category instead, such as W55.01XA, W55.01XD, W55.01XS, and W55.03XA.

Code Identity

ICD-10-CM Code
W55
Billable Status
No — Non-Billable Category
Code Describes
Contact with other mammals
Short Description
Contact with other mammals
Same as the full description in the CMS dataset.
Chapter
W50-W64
Exposure to animate mechanical forces

Code Classification

ChapterV01–Y99External causes of morbidity and mortality
SectionW50-W64Exposure to animate mechanical forces
CategoryW55Contact with other mammals
This CodeW55Contact with other mammals

Specific Coding for Contact with other mammalsOverview

Non-specific codes like W55 require more characters. Use one of these billable codes instead:

  • W55.0 for Contact with cat

  • W55.01 for Bitten by cat

  • W55.03 for Scratched by cat

  • W55.09 for Other contact with cat

  • W55.1 for Contact with horse

  • W55.11 for Bitten by horse

  • W55.12 for Struck by horse

  • W55.19 for Other contact with horse

  • W55.2 for Contact with cow

  • W55.21 for Bitten by cow

  • W55.22 for Struck by cow

  • W55.29 for Other contact with cow

  • W55.3 for Contact with other hoof stock

  • W55.31 for Bitten by other hoof stock

  • W55.32 for Struck by other hoof stock

  • W55.39 for Other contact with other hoof stock

  • W55.4 for Contact with pig

  • W55.41 for Bitten by pig

  • W55.42 for Struck by pig

  • W55.49 for Other contact with pig

  • W55.5 for Contact with raccoon

  • W55.51 for Bitten by raccoon

  • W55.52 for Struck by raccoon

  • W55.59 for Other contact with raccoon

  • W55.8 for Contact with other mammals

  • W55.81 for Bitten by other mammals

  • W55.82 for Struck by other mammals

  • W55.89 for Other contact with other mammals

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to W55: its own notes plus those printed at block W50-W64 and Chapter 20. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

  • contact with saliva, feces or urine of mammal

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

On W55 itself
  • animal being ridden- see transport accidents
  • bitten or struck by dog (W54)
  • bitten or struck by rodent (W53.-)
  • contact with marine mammals (W56.-)
From Block W50-W64 Exposure to animate mechanical forces applies to 336 codes
  • Toxic effect of contact with venomous animals and plants (T63.-)

Notes

General instructions on how these codes are used.

From Chapter 20 (V00-Y99) External causes of morbidity and mortality applies to 7,461 codes
  • This chapter permits the classification of environmental events and circumstances as the cause of injury, and other adverse effects. Where a code from this section is applicable, it is intended that it shall be used secondary to a code from another chapter of the Classification indicating the nature of the condition. Most often, the condition will be classifiable to Chapter 19, Injury, poisoning and certain other consequences of external causes (S00-T88). Other conditions that may be stated to be due to external causes are classified in Chapters I to XVIII. For these conditions, codes from Chapter 20 should be used to provide additional information as to the cause of the condition.

7th Character

Every code in the category takes a 7th character from the listed values, with the placeholder X filling any empty positions before it.

  • The appropriate 7th character is to be added to each code from category W55
Values for category W55 Encounter: Initial, Subsequent, Sequela
  • Ainitial encounter
  • Dsubsequent encounter
  • Ssequela

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About W55Overview

What is the ICD-10 code for contact with other mammals?

W55 is the ICD-10-CM category for contact with other mammals, but it is a non-billable header: claims need a more specific code from this category, listed on this page.

Is W55 (Contact with other mammals) a billable code?

No. This is a category header that groups the codes for contact with other mammals, and headers cannot be submitted on claims. Claims for contact with other mammals need a more specific code from this category, such as W55.01XA, W55.01XD, and W55.01XS.

Can W55 be reported with W54?

Not as a rule. The Excludes1 note on W55 lists "bitten or struck by dog (W54)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).