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N63 ICD-10-CM Code: Unspecified lump in breast

Compare with another code for N63Check this code on a claim

Billing Status: NO. This is a non-billable ICD-10-CM code: report a more specific billable code beneath it.

Coding at a Glance

Official instructions
1 inclusion term · 1 Excludes1

What these terms mean →

Category · FY2027A non-billable heading in the tabular list: report a more specific code beneath it.

What you need to know

Source: CMS/NCHS Official ICD-10-CM tabular notes, quoted. From the CMS/NCHS tabular list for the release in force. A note the category or block publishes applies to this code too, and is marked with where it comes from.

Excludes1from N60-N65Not reported with this code unless documented as unrelated
  • disorders of breast associated with childbirth (O91-O92)
IncludesWhat this code covers
  • Nodule(s) NOS in breast

Where it sits Source: CMS/NCHS

Under:Chapter 14: Diseases of the Genitourinary SystemN60-N65 Disorders of breast

Codes under N63 (5)

  • N63.0Unspecified lump in unspecified breastBillable
  • N63.1Unspecified lump in the right breastNot billable
  • N63.2Unspecified lump in the left breastNot billable
  • N63.3Unspecified lump in axillary tailNot billable
  • N63.4Unspecified lump in breast, subareolarNot billable

CompareCheck ClaimView Related Codes

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for N63 in the official ICD-10-CM tabular list, quoted as published.

Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2027Effective: October 1, 2026

Trace:FY2027 changesChange historyRelease, file and checksum

Notes without a marker are published on N63 itself; “inherited from” names the category or block whose note applies here.

Inclusion Terms

Alternative terms the tabular list files under this code.

  • Nodule(s) NOS in breast

Excludes1 — Not Coded Here

Conditions generally not reported together with this code (Excludes1) -- an error unless the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).

Source: inherited from N60-N65

Coder workflow for N63

MedCoder structured workflow — derived from this code’s own official record

Before you code N63

  1. N63 is not reportable as written. Select the more specific code beneath it that the documentation supports. Codes are reported to the highest level of specificity the classification provides (Guidelines I.B.2).

    ReviewN63.0, N63.1, N63.2, N63.3, N63.4

    See the relationships section · Guide: How to choose an ICD-10-CM code →

  2. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with the code beneath N63. Excludes1 conditions are not reported together with this code unless the record shows they are unrelated (Guidelines I.A.12.a).

    See the official tabular notes

Choose the right path

  1. Does the documentation support one of the more specific codes beneath N63?
    Yes → Select that code and continue the checks below on its own page.
    No → N63 cannot be reported as written. Where the codes beneath it include an unspecified code, that code applies when the record goes no further; otherwise query for the missing detail.

    ReviewN63.0, N63.1, N63.2, N63.3, N63.4

  2. Does the documentation support a condition named in N63’s Excludes1 note?
    Yes → Do not simply proceed: review the excluded code. Both are reported only when the record shows the two conditions are unrelated.
    No → Continue.

Report the code beneath N63 that the documentation supports, not N63 itself. Then confirm that code is valid for the date of service on its own page.

Documentation check

The provider’s diagnostic statement
Codes are assigned from the provider’s documented diagnosis, not from clinical criteria, test values or a medication list (Guidelines I.A.19).
Any detail beyond this code’s title
What the record states that a more specific code would capture — or its absence, which itself supports the unspecified code.

Official instructions as workflow

  • Excludes1 — check before selecting N63(1 note)

    Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with N63: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

    See the official tabular notes · Guidelines I.A.12.a

Coding decision scenarios

Pattern scenarios for this code’s structure — decision rules, not clinical cases

Documentation: The provider documents the condition in the terms of this code’s title and records no further detail.

Coding question: Is a more specific code supportable?

Path: No sibling in this subcategory is more specific; look the documented detail up in the Alphabetic Index.

Reason: A more specific code needs documentation of the distinguishing element; without it the unspecified code is appropriate, and a provider query is the route to specificity (Guidelines I.A.9.b, I.B.18).

Documentation: Both the condition N63 describes and a condition named in its Excludes1 note are documented for the same encounter.

Coding question: Can both codes be reported?

Path: Review the Excludes1 note and the excluded code, and look for a provider statement on whether the two conditions are related.

Reason: Excludes1 means the two are not coded together; the exception is when the record shows the conditions are unrelated to each other (Guidelines I.A.12.a).

Every row is derived from this code’s own record — its title, tabular notes, 7th-character family and same-category siblings — with fixed MedCoder wording; nothing is inferred about a patient. The official notes and guideline text are in the sections each row links to, and they control.

Don’t confuse N63 with…

MedCoder analysis — pairs from this code’s official notes, distinctions written by MedCoder

The codes most likely to be picked instead of N63 — named in its own official notes, or sharing its laterality or encounter family — with what separates them and which documentation moves the case. Each links to the full comparison.

  • O91— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of disorders of breast associated with childbirth moves the case to O91; the two are not reported together unless documented as unrelated.

    Full comparison: N63 vs O91 →

  • O92— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of disorders of breast associated with childbirth moves the case to O92; the two are not reported together unless documented as unrelated.

    Full comparison: N63 vs O92 →

Relationships are read from this code's own official notes, its laterality siblings and its encounter family; the wording of each distinction is MedCoder editorial, and the documentation named in each “what moves you there” line is the official note phrase or sibling title itself. Source: CMS ICD-10-CM tabular instructional notes; ICD-10-CM Official Guidelines, Section I.A.12.a.

Coding context

Guidelines, coding notes, decision aids, relationships (with MS-DRG and CCSR classification), hierarchy, HCC, coverage and the context map: what a coder reaches for after the core. Each section names whether it is official source data, a MedCoder-derived relationship or MedCoder editorial.

Code Overview

Unspecified lump in breast is a non-billable ICD-10-CM category code (N63). A more specific billable subcode must be selected for claims submission.

MedCoder summary Summary composed by MedCoder from this code's official ICD-10-CM record. The tabular instructional notes themselves appear verbatim below.

Verify Before Coding

From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim in Claim Check.

Relationships & Classification

MedCoder-derived relationships — computed from published CMS and AHRQ datasets

Other codes that name N63 or its code family, from the CMS ICD-10-CM tabular instructional notes. Tabular-note edges are stored at the code family level that carries each note.

Referenced by 1 Excludes2 note: R22.2 — Localized swelling, mass and lump, trunk.

These codes’ tabular lists name this diagnosis as distinct — both may be reported when both are documented.

Clinical classification (AHRQ CCSR):GEN017 — Nonmalignant breast conditions (default).

Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses. Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality.

Related Codes

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical category (Nonmalignant breast conditions).

N60.92 — Unspecified benign mammary dysplasia of left breast, N60.99 — Unspecified benign mammary dysplasia of unspecified breast, N61 — Inflammatory disorders of breast, N61.0 — Mastitis without abscess, N61.1 — Abscess of the breast and nipple, N61.20 — Granulomatous mastitis, unspecified breast, N61.21 — Granulomatous mastitis, right breast, N61.22 — Granulomatous mastitis, left breast, N61.23 — Granulomatous mastitis, bilateral breast, N62 — Hypertrophy of breast, N63.0 — Unspecified lump in unspecified breast, N63.10 — Unspecified lump in the right breast, unspecified quadrant, N63.11 — Unspecified lump in the right breast, upper outer quadrant, N63.12 — Unspecified lump in the right breast, upper inner quadrant, N63.13 — Unspecified lump in the right breast, lower outer quadrant, N63.14 — Unspecified lump in the right breast, lower inner quadrant, N63.15 — Unspecified lump in the right breast, overlapping quadrants, N63.20 — Unspecified lump in the left breast, unspecified quadrant, N63.21 — Unspecified lump in the left breast, upper outer quadrant, N63.22 — Unspecified lump in the left breast, upper inner quadrant, +65 more

Contextual Map

Every relationship of N63 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.

Run N63 with these 3 related codes in Claim Check

Hierarchy

Excludes1

Referenced by Excludes2 notes

Clinical classification (CCSR)

Nearest codes (21)

Change history (2)

Reference

Index terms and tables, published questions and FAQ, every source behind this page with its release and checksum, the date-of-service check and the complete change history.

Common coding questions

MedCoder editorial

Can N63 be billed directly?

No. N63 (Unspecified lump in breast) is a non-billable ICD-10-CM category code. A more specific billable subcode must be selected based on clinical documentation.

Sources for this page

Codes, titles, notes, index terms and mappings on this page are transcribed from the datasets below. Relationships MedCoder computed and text MedCoder wrote are labelled where they appear.

Code, title, tabular notes and index terms Official source data
CMS/CDC ICD-10-CM FY2027 tabular list, index and tables, effective October 1, 2026 Release, file and checksum · Publisher’s page
Claim edits Official source data
CMS Definitions of Medicare Code Edits — v44.0 (October 2026) Release, file and checksum · Publisher’s page
Change history and date-of-service validity Official source data
CMS ICD-10-CM release addenda, ingested release by release into the change ledger Release, file and checksum · Publisher’s page
Comparisons, relationships and the contextual map MedCoder-derived relationship
Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears
Summary and FAQ answers MedCoder editorial explanation
Written by MedCoder to explain the sources above: drafted with AI assistance, checked by a person against the release files, and labelled as MedCoder text where it appears. Not official text.

Current data releases:ICD-10-CM FY2027 · ICD-10-PCS FY2027 · HCPCS October 2026 · MS-DRG v44 · Medicare Code Editor v44.0 · NCCI PTP Q4 2026 · MUE Q4 2026 · NCD code lists 2026-01 · LCD export September 28, 2026 · All releases and sources

Labels on this page: Official source data · MedCoder-derived relationship · MedCoder editorial explanation. How to read the labels · All data sources and release dates · CMS coding rules

Cite this page

Reference this page in a research guide, syllabus or article. The release is included because code content changes each year.

MedCoder.ai. "N63 — Unspecified lump in breast." ICD-10-CM FY2027. https://medcoder.ai/icd10/code/n63-unspecified-lump-in-breast

Change history

  • FY2018 — October 1, 2017
    Became a non-billable header
    FY2018 changes
  • FY2016 — October 1, 2015
    In the code set at ICD-10-CM adoption
    Unspecified lump in breast

Nearest Codes in This Family

Official ICD-10-CM classifications closest to N63 in its code family, with their registry titles.