N64.1 – Fat necrosis of breast

ICD-10-CM 2027 diagnosis code · Disorders of breast

Billable code

ICD-10-CM code N64.1

Code: N64.1 (claims format: N641)
Description: Fat necrosis of breast
Billable: Yes – valid for HIPAA-covered transactions
Valid for: Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter: 14. Diseases of the genitourinary system (N00-N99)
Block: N60-N65 Disorders of breast
Parent codes: N64

Notes for N64.1

Applicable to:

Fat necrosis (segmental) of breast

Code first:

breast necrosis due to breast graft (T85.898)

Notes inherited from parent codes

Instructional notes at a category or block level apply to every code below it.

N64 – Other disorders of breast

Excludes2 (not included here):

mechanical complication of breast prosthesis and implant (T85.4-)

Block N60-N65

Excludes1 (not coded here):

disorders of breast associated with childbirth (O91-O92)

Index terms for N64.1

Entries in the ICD-10-CM alphabetic index that lead to this code:

Related codes in N64

N64.0 – Fissure and fistula of nippleBillable
N64.2 – Atrophy of breastBillable
N64.3 – Galactorrhea not associated with childbirthBillable
N64.4 – MastodyniaBillable
N64.5 – Other signs and symptoms in breastHeader
N64.8 – Other specified disorders of breastHeader
N64.9 – Disorder of breast, unspecifiedBillable

Frequently asked questions

What is ICD-10 code N64.1?

N64.1 is the ICD-10-CM code for fat necrosis of breast, in the block N60-N65 (Disorders of breast).

Is N64.1 a billable code?

Yes. N64.1 is a billable/specific code that can be used to indicate a diagnosis for reimbursement purposes.

What category does N64.1 belong to?

It belongs to category N64 – Other disorders of breast.

Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.