Contact with other mammals (W55) ICD-10-CM
The W55 code range covers contact with other mammals with 92 ICD-10-CM diagnosis codes. 63 of them are billable and valid for claim submission in fiscal year 2026, and the category headers group them but cannot themselves be billed.
Includes
This note appears immediately under a three character code title to further define, or give examples of, the content of the category.
- contact with saliva, feces or urine of mammal
Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
- animal being ridden- see transport accidents
- bitten or struck by dog W54
- bitten or struck by rodent W53
- contact with marine mammals W56
7th Character Note
Certain ICD-10-CM categories have applicable 7th characters. The applicable 7th character is required for all codes within the category, or as the notes in the Tabular List instruct. The 7th character must always be the 7th character in the data field. If a code that requires a 7th character is not 6 characters, a placeholder X must be used to fill in the empty characters.
- The appropriate 7th character is to be added to each code from category W55
7th Character
Indicates that a seventh character is to be assigned to codes in a subcategory.
- A - initial encounter
- D - subsequent encounter
- S - sequela
Codes in the W55 Range 92 codes · 63 billable
- W55 Contact with other mammalsNon-billable
- W55.0 Contact with catNon-billable
- W55.01 Bitten by catNon-billable
- W55.01XA Bitten by cat, initial encounter
- W55.01XD Bitten by cat, subsequent encounter
- W55.01XS Bitten by cat, sequela
- W55.03 Scratched by catNon-billable
- W55.03XA Scratched by cat, initial encounter
- W55.03XD Scratched by cat, subsequent encounter
- W55.03XS Scratched by cat, sequela
- W55.09 Other contact with catNon-billable
- W55.09XA Other contact with cat, initial encounter
- W55.09XD Other contact with cat, subsequent encounter
- W55.09XS Other contact with cat, sequela
- W55.1 Contact with horseNon-billable
- W55.11 Bitten by horseNon-billable
- W55.11XA Bitten by horse, initial encounter
- W55.11XD Bitten by horse, subsequent encounter
- W55.11XS Bitten by horse, sequela
- W55.12 Struck by horseNon-billable
- W55.12XA Struck by horse, initial encounter
- W55.12XD Struck by horse, subsequent encounter
- W55.12XS Struck by horse, sequela
- W55.19 Other contact with horseNon-billable
- W55.19XA Other contact with horse, initial encounter
- W55.19XD Other contact with horse, subsequent encounter
- W55.19XS Other contact with horse, sequela
- W55.2 Contact with cowNon-billable
- W55.21 Bitten by cowNon-billable
- W55.21XA Bitten by cow, initial encounter
- W55.21XD Bitten by cow, subsequent encounter
- W55.21XS Bitten by cow, sequela
- W55.22 Struck by cowNon-billable
- W55.22XA Struck by cow, initial encounter
- W55.22XD Struck by cow, subsequent encounter
- W55.22XS Struck by cow, sequela
- W55.29 Other contact with cowNon-billable
- W55.29XA Other contact with cow, initial encounter
- W55.29XD Other contact with cow, subsequent encounter
- W55.29XS Other contact with cow, sequela
- W55.3 Contact with other hoof stockNon-billable
- W55.31 Bitten by other hoof stockNon-billable
- W55.31XA Bitten by other hoof stock, initial encounter
- W55.31XD Bitten by other hoof stock, subsequent encounter
- W55.31XS Bitten by other hoof stock, sequela
- W55.32 Struck by other hoof stockNon-billable
- W55.32XA Struck by other hoof stock, initial encounter
- W55.32XD Struck by other hoof stock, subsequent encounter
- W55.32XS Struck by other hoof stock, sequela
- W55.39 Other contact with other hoof stockNon-billable
- W55.39XA Other contact with other hoof stock, initial encounter
- W55.39XD Other contact with other hoof stock, subsequent encounter
- W55.39XS Other contact with other hoof stock, sequela
- W55.4 Contact with pigNon-billable
- W55.41 Bitten by pigNon-billable
- W55.41XA Bitten by pig, initial encounter
- W55.41XD Bitten by pig, subsequent encounter
- W55.41XS Bitten by pig, sequela
- W55.42 Struck by pigNon-billable
- W55.42XA Struck by pig, initial encounter
- W55.42XD Struck by pig, subsequent encounter
- W55.42XS Struck by pig, sequela
- W55.49 Other contact with pigNon-billable
- W55.49XA Other contact with pig, initial encounter
- W55.49XD Other contact with pig, subsequent encounter
- W55.49XS Other contact with pig, sequela
- W55.5 Contact with raccoonNon-billable
- W55.51 Bitten by raccoonNon-billable
- W55.51XA Bitten by raccoon, initial encounter
- W55.51XD Bitten by raccoon, subsequent encounter
- W55.51XS Bitten by raccoon, sequela
- W55.52 Struck by raccoonNon-billable
- W55.52XA Struck by raccoon, initial encounter
- W55.52XD Struck by raccoon, subsequent encounter
- W55.52XS Struck by raccoon, sequela
- W55.59 Other contact with raccoonNon-billable
- W55.59XA Other contact with raccoon, initial encounter
- W55.59XD Other contact with raccoon, subsequent encounter
- W55.59XS Other contact with raccoon, sequela
- W55.8 Contact with other mammalsNon-billable
- W55.81 Bitten by other mammalsNon-billable
- W55.81XA Bitten by other mammals, initial encounter
- W55.81XD Bitten by other mammals, subsequent encounter
- W55.81XS Bitten by other mammals, sequela
- W55.82 Struck by other mammalsNon-billable
- W55.82XA Struck by other mammals, initial encounter
- W55.82XD Struck by other mammals, subsequent encounter
- W55.82XS Struck by other mammals, sequela
- W55.89 Other contact with other mammalsNon-billable
- W55.89XA Other contact with other mammals, initial encounter
- W55.89XD Other contact with other mammals, subsequent encounter
- W55.89XS Other contact with other mammals, sequela
About the W55 Code Range
The ICD-10 code section W55 covers injuries related to contact with various mammals, such as cats, horses, cows, pigs, raccoons, and other hoof stock. These codes specify the type of contact, including bites, scratches, being struck, or other forms of accidental physical contact, and are used to document the cause of injury.
This set of codes allows healthcare providers and medical coders to identify specific incidents like a cat bite (e.g., W55.01XA for initial encounter of cat bite) or a horse strike (W55.12XA). It also distinguishes between the initial treatment, subsequent visits, and long-term complications (sequela) of such injuries. For example, a cat scratch, also known as cat scratch injury or scratch by animal claw, is coded with W55.03 and its extensions. Other codes capture less common mammal contacts, such as bites from large carnivores or punctures by quills (W55.81XA and W55.89XA). These detailed classifications help ensure precise recording of injury mechanisms, supporting accurate documentation of animal-related trauma and related medical care.
Questions About This Page
How many billable codes are in the W55 range?
Of the 92 codes in this range, 63 are billable and valid for claim submission from October 1, 2025 through September 30, 2026. Category header codes group them but cannot be reported on claims.
What does the W55 range classify?
The range classifies contact with other mammals. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2026 ICD-10-CM Tabular List and order file, effective October 1, 2025 through September 30, 2026.
