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ICD-10-CM · FY 2026 APRIL UPDATE

T20.4

Corrosion of unspecified degree of head, face, and neck

Diagnosis reference

Nonbillable category

This entry is a category or subcategory. Choose the appropriate billable descendant based on the clinical documentation.

Effective periodOctober 1, 2026–September 30, 2027
SourceCMS ICD-10-CM order file
ClassificationDiagnosis · clinical modification

Related entries

Up to 30 descendants in this category

CODEDESCRIPTIONTYPE
T20.40Corrosion of unspecified degree of head, face, and neck, unspecified siteCategory
T20.40XACorrosion of unspecified degree of head, face, and neck, unspecified site, initial encounterBillable
T20.40XDCorrosion of unspecified degree of head, face, and neck, unspecified site, subsequent encounterBillable
T20.40XSCorrosion of unspecified degree of head, face, and neck, unspecified site, sequelaBillable
T20.41Corrosion of unspecified degree of ear [any part, except ear drum]Category
T20.411Corrosion of unspecified degree of right ear [any part, except ear drum]Category
T20.411ACorrosion of unspecified degree of right ear [any part, except ear drum], initial encounterBillable
T20.411DCorrosion of unspecified degree of right ear [any part, except ear drum], subsequent encounterBillable
T20.411SCorrosion of unspecified degree of right ear [any part, except ear drum], sequelaBillable
T20.412Corrosion of unspecified degree of left ear [any part, except ear drum]Category
T20.412ACorrosion of unspecified degree of left ear [any part, except ear drum], initial encounterBillable
T20.412DCorrosion of unspecified degree of left ear [any part, except ear drum], subsequent encounterBillable
T20.412SCorrosion of unspecified degree of left ear [any part, except ear drum], sequelaBillable
T20.419Corrosion of unspecified degree of unspecified ear [any part, except ear drum]Category
T20.419ACorrosion of unspecified degree of unspecified ear [any part, except ear drum], initial encounterBillable
T20.419DCorrosion of unspecified degree of unspecified ear [any part, except ear drum], subsequent encounterBillable
T20.419SCorrosion of unspecified degree of unspecified ear [any part, except ear drum], sequelaBillable
T20.42Corrosion of unspecified degree of lip(s)Category
T20.42XACorrosion of unspecified degree of lip(s), initial encounterBillable
T20.42XDCorrosion of unspecified degree of lip(s), subsequent encounterBillable
T20.42XSCorrosion of unspecified degree of lip(s), sequelaBillable
T20.43Corrosion of unspecified degree of chinCategory
T20.43XACorrosion of unspecified degree of chin, initial encounterBillable
T20.43XDCorrosion of unspecified degree of chin, subsequent encounterBillable
T20.43XSCorrosion of unspecified degree of chin, sequelaBillable
T20.44Corrosion of unspecified degree of nose (septum)Category
T20.44XACorrosion of unspecified degree of nose (septum), initial encounterBillable
T20.44XDCorrosion of unspecified degree of nose (septum), subsequent encounterBillable
T20.44XSCorrosion of unspecified degree of nose (septum), sequelaBillable
T20.45Corrosion of unspecified degree of scalp [any part]Category

Use the complete reference

This reference does not reproduce the full tabular hierarchy, inclusion notes, Excludes1/2 notes, sequencing instructions, or seventh-character rules. Review the official tables and coding guidelines.

Open official CMS files

ICD-10-CM codes describe diagnoses. They do not have an independent Medicare PFS reimbursement amount, and billability alone does not establish coverage.