2026 ICD-10-CM Diagnosis Code N63Unspecified lump in breast

ICD-10-CM Codes›N00–N99›N60-N65›N63

ICD-10-CM N63
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

N63 is a non-billable ICD-10-CM category code for unspecified lump in breast, so it cannot be submitted on claims. Use a more specific code from this category instead, such as N63.0, N63.10, N63.11, and N63.12. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Nonmalignant breast conditions.

This medical diagnosis code is frequently used in OB/GYN medical specialties to designate conditions such lump in breast and other disorders of the breast.

Code Identity

ICD-10-CM Code
N63
Billable Status
No — Non-Billable Category
Code Describes
Unspecified lump in breast
Chapter
N60-N65
Disorders of breast

Code Classification

ChapterN00–N99Diseases of the genitourinary system
SectionN60-N65Disorders of breast
CategoryN63Unspecified lump in breast
This CodeN63Unspecified lump in breast

Specific Coding for Unspecified lump in breastOverview

Non-specific codes like N63 require more characters. Use one of these billable codes instead:

  • Use N63.0 for Unspecified lump in unspecified breast

  • N63.1 for Unspecified lump in the right breast

  • Use N63.10 for Unspecified lump in the right breast, unspecified quadrant

  • Use N63.11 for Unspecified lump in the right breast, upper outer quadrant

  • Use N63.12 for Unspecified lump in the right breast, upper inner quadrant

  • Use N63.13 for Unspecified lump in the right breast, lower outer quadrant

  • Use N63.14 for Unspecified lump in the right breast, lower inner quadrant

  • Use N63.15 for Unspecified lump in the right breast, overlapping quadrants

  • N63.2 for Unspecified lump in the left breast

  • Use N63.20 for Unspecified lump in the left breast, unspecified quadrant

  • Use N63.21 for Unspecified lump in the left breast, upper outer quadrant

  • Use N63.22 for Unspecified lump in the left breast, upper inner quadrant

  • Use N63.23 for Unspecified lump in the left breast, lower outer quadrant

  • Use N63.24 for Unspecified lump in the left breast, lower inner quadrant

  • Use N63.25 for Unspecified lump in the left breast, overlapping quadrants

  • N63.3 for Unspecified lump in axillary tail

  • Use N63.31 for Unspecified lump in axillary tail of the right breast

  • Use N63.32 for Unspecified lump in axillary tail of the left breast

  • N63.4 for Unspecified lump in breast, subareolar

  • Use N63.41 for Unspecified lump in right breast, subareolar

  • Use N63.42 for Unspecified lump in left breast, subareolar

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • Nodule(s) NOS in breast

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR GEN017
Nonmalignant breast conditions
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Breast Diseases

Breast diseases include various conditions and changes in your breast. Most women experience breast changes at some time. Your age, hormone levels, and medicines you take may cause lumps, bumps, and discharges of fluids that are not breast milk.

The full article covers:

  • What are breast diseases?
  • What are the symptoms of breast disease?
  • How are breast diseases diagnosed?
  • What are the treatments for breast disease?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About N63Overview

Is N63 (Unspecified lump in breast) a billable code?

No. This is a category header that groups the codes for unspecified lump in breast, and headers cannot be submitted on claims. Claims for unspecified lump in breast need a more specific code from this category, such as N63.0, N63.10, and N63.11.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.