CPT® Code 19318

Quick Reference

• Code definition: CPT 19318 covers the complete breast reduction (reduction mammaplasty) procedure, including excision of excess glandular tissue, fat, and skin; repositioning of the nipple-areola complex on a pedicle; and skin closure to reshape the breast mound.
• Key billing rule: MUE = 1 per breast per session; bilateral procedures require modifier 50 (or separate LT/RT lines), not two units on the same line. The bilateral surgery indicator is 1, meaning CMS pays 150% of the single-breast allowable for bilateral cases.
• Modifier essentials: Modifier 50 applies to same-session bilateral reduction (56% of claims). Use LT/RT when payers prefer line-level laterality. Modifier 22 requires documentation of substantially increased complexity; modifier 62 is payable with supporting documentation but team surgery (modifier 66) is prohibited.
• Documentation must-have: The operative report must record the weight in grams of tissue removed from each breast. Missing tissue weight is the single most common cause of post-payment audit recoupment and payer denial.
• Top confusion point: Mastopexy components (skin excision, nipple repositioning) are integral to 19318. Billing 19316 alongside 19318 for the same breast at the same session requires documentation of a separately indicated, distinct procedure beyond what 19318 already encompasses.
• Payer alert: Medicare treats bilateral breast reduction as cosmetic and non-covered except when performed on the contralateral breast for symmetry following mastectomy reconstruction, which is covered under the Women's Health and Cancer Rights Act. Commercial payers typically cover medically necessary cases with prior authorization and tissue-weight thresholds, most commonly 500 g or more per breast.
• Global period: 90-day major surgery global period applies. Separately billing E/M visits within the global period requires modifier 24 (unrelated E/M) or modifier 79 (unrelated procedure).

When to Use This Code

Clinical indications. CPT 19318 is the correct code when a surgeon removes excess glandular tissue, fat, and skin from one or both breasts and repositions the nipple-areola complex to a higher location on the breast mound. The standard approach uses a circumareolar incision extending vertically to the inframammary fold (Wise/anchor or vertical/lollipop pattern). Liposuction of the axillary area may occur during the same operative session.

Medical necessity vs. cosmetic. For payer coverage purposes, the operative indication must fall into one of two buckets: (1) symptomatic macromastia with documented physical sequelae, or (2) breast symmetry after mastectomy reconstruction. Symptoms that support medical necessity include chronic back pain, cervicalgia, shoulder pain with bra-strap grooving, intertrigo under the inframammary fold, and paresthesias from brachial plexus compression. Documentation must connect the symptom to the breast size and demonstrate that conservative measures (specialized brassiere support, physical therapy, dermatologic treatment for intertrigo) failed before surgery was pursued.

Technique variants within 19318. The code covers pedicle-based nipple-areola repositioning, which preserves blood supply and nerve function. When the breast is extremely large or pendulous and the nipple must be completely detached and regrafted as a free graft, 19350 (nipple/areola reconstruction) may be separately reportable. Whether free nipple graft is separately billable requires payer-specific verification and clear operative documentation distinguishing the reconstruction component from the reduction.

Gynecomastia vs. macromastia. CPT 19318 covers breast-size reduction for conditions other than gynecomastia. The CPT codebook directs coders to 19318 specifically when breast tissue is removed for size reduction rather than cancer treatment or prevention. ICD-10-CM N62 (Hypertrophy of breast) is the appropriate primary diagnosis and covers gynecomastia, hypertrophy NOS, and massive pubertal hypertrophy.

Setting. This is a physician service code (PC/TC indicator 0). It appears on the ASC-approved procedure list with payment based on OPPS relative weight, so it is commonly performed in both hospital outpatient and ASC settings.

Code Differentiation Table

The most critical differentiator is between 19318 and 19316. A mastopexy reshapes and lifts the breast through skin excision and nipple repositioning; a breast reduction does the same while also removing a substantial volume of glandular tissue. When both procedures are performed on the same breast at the same session, the CPT codebook instructs against billing 19380 (revision of reconstructed breast) with 19318 for the same breast, and the overlap between 19316 and 19318 requires that any simultaneous billing be supported by documentation of two distinct, independently indicated procedures.

Billing & Modifier Rules

Bilateral reporting. The CMS bilateral surgery indicator for 19318 is 1, meaning the standard 150% payment adjustment applies for bilateral same-session procedures. Bill 19318-50 as a single line, or report 19318-LT and 19318-RT on separate lines on the same date of service. Never bill two units of 19318 on the same line without a bilateral modifier; this causes claim rejection or overpayment.

Modifier 22. Use modifier 22 only when the operative complexity is substantially greater than typical for 19318: massively enlarged breasts requiring prolonged operative time, free nipple grafting due to extreme ptosis, or significant comorbidities materially increasing surgical risk. Attach a cover letter documenting the specific factors driving increased complexity. Routine bilateral reduction does not support modifier 22.

Co-surgeons (modifier 62). CMS indicator = 1: co-surgeons are payable with supporting documentation. Both surgeons must report 19318-62 and document their distinct operative contributions. Team surgery (modifier 66) has a CMS indicator of 0 and is not permitted for this code.

Assistant surgeon (modifiers 80, 82). CMS indicator = 2 indicates that payment restrictions for assistants at surgery do NOT apply. An assistant surgeon is payable at the standard assistant rate. Report with modifier 80 (or 82 when a qualified resident is unavailable).

Global period management. The 90-day global period includes all pre- and postoperative care. E/M visits for reasons unrelated to the breast reduction within the global period require modifier 24. Return to the OR for a related complication (e.g., wound dehiscence) requires modifier 78; unrelated procedures during the global period require modifier 79.

Axillary liposuction. When 15877 is separately documented and performed at the same session, append modifier 51 to 15877 as the secondary procedure. NCCI PTP edit status for this pair must be verified against current CMS NCCI tables before billing both codes.

Documentation Essentials

Operative report requirements. The single most audited element is tissue weight: the operative report must state the weight in grams removed from each breast. Without a recorded weight, payers cannot verify compliance with their threshold criteria (commonly 500 g per breast for commercial plans) and will deny on audit regardless of whether the surgery was clinically justified. Additional required elements include:

• Incision technique (Wise pattern, vertical, periareolar) and specific anatomical landmarks
• Method of nipple-areola repositioning (pedicle type, or free graft with rationale)
• Laterality (right, left, or bilateral)
• Description of any additional procedures performed (axillary liposuction, concomitant mastopexy component) with separate operative documentation if separately billed
• Intraoperative findings supporting the medical necessity diagnosis (e.g., degree of ptosis, tissue consistency)

Pre-operative documentation. The medical record should establish: duration and severity of symptoms (back pain, cervicalgia, shoulder grooving, intertrigo); prior conservative treatment and its failure; photographs demonstrating the degree of hypertrophy; and the physician's medical necessity determination linking the symptom burden to surgical intervention. Some MAC LCDs and commercial policies also require BMI documentation and evidence that weight reduction was considered or attempted.

Audit triggers specific to 19318. Auditors flag claims where: (1) the operative report lacks tissue weights; (2) the diagnosis is coded only as N62 without secondary codes supporting functional impairment (e.g., M54.2, M54.59, L30.4); (3) 19316 and 19318 are billed together for the same breast without distinct documentation; and (4) bilateral modifier is missing while two units are billed.

Medicare, Commercial & Medicaid Payer Rules

Medicare. Medicare considers bilateral breast reduction cosmetic under SSA §1862(a)(10) and does not cover it absent a specific exception. The primary covered exception is contralateral breast reduction performed for symmetry following mastectomy and reconstruction, which is mandated by the Women's Health and Cancer Rights Act of 1998. Coverage determination is governed by MAC-level Local Coverage Determinations rather than a national NCD. Coders should search the CMS Medicare Coverage Database by jurisdiction for the applicable LCD (search terms: "reduction mammaplasty" or "breast reduction"). MAC LCDs commonly specify minimum tissue resection thresholds, BMI criteria, and required documentation of conservative treatment failure. The ASC payment indicator confirms 19318 is payable in ASC settings.

Commercial payers. Most commercial plans cover medically necessary reduction mammaplasty with prior authorization. Coverage criteria typically parallel MAC LCD requirements: documented symptoms, tissue weight thresholds (commonly 500 g or more per breast), failure of conservative management, and pre-operative photographs. Prior authorization must be obtained before surgery; retroactive authorization is rarely granted for elective surgical procedures. Verify plan-specific thresholds before surgery, as some plans use body-surface-area-adjusted formulas rather than a flat gram threshold.

Medicaid. State Medicaid programs vary. Many cover medically necessary reduction mammaplasty with prior authorization, but coverage criteria, documentation requirements, and tissue weight thresholds differ by state. Managed Medicaid plans may impose additional restrictions beyond the base state policy.

Common Denials & Prevention

Missing tissue weight documentation Payer auditors and MAC contractors routinely recoup payments when the operative report does not document the weight of tissue removed. This is the most preventable denial for 19318. Prevention: confirm operative reports are templated to include tissue weight from pathology or intraoperative scale measurement before claim submission. Do not release the claim until the operative report is complete.

Medical necessity not established Payers deny when the claim lacks documentation connecting the diagnosis to a functional impairment. Coding N62 alone without secondary diagnosis codes for the specific symptoms (back pain, cervicalgia, intertrigo) does not adequately support medical necessity. Prevention: code all documented functional symptoms as secondary diagnoses. Ensure the pre-operative notes and operative report explicitly link the breast size to the symptom burden.

Incorrect bilateral reporting Billing 19318 with two units on a single line (instead of modifier 50 or LT/RT) triggers claim rejection or system-level denials. Prevention: bill 19318-50 as a single line, or use separate LT/RT lines depending on payer preference. Verify payer billing guidelines for bilateral reporting before submission.

Bundling denial: 19316 with 19318 When both mastopexy and breast reduction are billed for the same breast at the same session without documentation of a separately indicated procedure, payers deny 19316 as included in 19318. Prevention: if a distinct mastopexy component was performed and separately documented, verify current NCCI PTP edit status before billing both. Attach operative documentation clearly describing the separate, independently indicated mastopexy procedure.

Medicare cosmetic denial Bilateral reduction billed to Medicare without a covered indication (e.g., symmetry after mastectomy) will be denied as cosmetic. Prevention: confirm Medicare coverage eligibility before scheduling. For symmetry-after-mastectomy cases, use N65.1 (Disproportion of reconstructed breast) as the primary diagnosis and document the mastectomy history and reconstruction in the medical record. Issue an ABN if the cosmetic determination applies and the patient wants to self-pay.

Coding Scenarios

Scenario: A 35-year-old woman with documented cervicalgia, bilateral shoulder grooving from bra straps, and chronic intertrigo under both inframammary folds undergoes bilateral reduction mammaplasty. The operative report records 620 g removed from the right breast and 580 g from the left. Prior authorization from a commercial plan was obtained preoperatively.

Correct coding: 19318-50 / N62 (primary), M54.2, L30.4

Why: Bilateral modifier 50 is used because both breasts were reduced at the same session (bilateral indicator = 1). Secondary diagnoses document the specific functional symptoms driving medical necessity beyond the hypertrophy diagnosis alone.

Scenario: A 58-year-old woman who underwent left mastectomy and TRAM flap reconstruction two years ago now has right breast size disproportionate to the reconstructed left breast. She undergoes right breast reduction for symmetry. She is enrolled in Medicare.

Correct coding: 19318-RT / N65.1 (primary)

Why: The WHCRA mandates coverage for symmetry procedures after mastectomy reconstruction. Use N65.1 (Disproportion of reconstructed breast) rather than N62 to identify this as a reconstructive symmetry procedure. The modifier RT documents the laterality; modifier 50 does not apply because only one breast was operated on. Medicare coverage documentation must reference the mastectomy history.

Scenario: During a bilateral reduction mammaplasty, the surgeon also performs separate suction-assisted lipectomy of the bilateral axillary regions to improve lateral contour. The operative report documents both the breast reduction and the axillary liposuction as distinct procedures with separate descriptions of technique and anatomical site.

Correct coding: 19318-50, 15877-51 (contingent on NCCI PTP edit verification) / N62 (primary), secondary symptom codes as applicable

Why: Axillary liposuction may be separately reportable when clearly documented as a distinct component. Modifier 51 applies to the secondary procedure under standard multiple-procedure rules. NCCI PTP edit status for the 19318/15877 pair must be confirmed before billing both; if an edit exists without a modifier indicator permitting override, the axillary liposuction cannot be separately reported.

Scenario: A surgeon performs bilateral reduction mammaplasty and documents skin excision and lifting components consistent with mastopexy in the same operative note. The coder considers billing both 19318-50 and 19316-50.

Correct coding: 19318-50 only / N62 (primary), secondary codes as applicable

Why: Mastopexy components are integral to breast reduction. The CPT codebook instructs that 19316 and 19318 should not be reported together for the same breast unless the mastopexy represents a separately indicated, distinctly documented procedure. When the operative note describes a single unified reduction with skin lifting, 19318 captures the complete service.

Related Codes

• 19316 (Mastopexy): breast lift without major tissue excision; often confused with 19318 for procedures with skin excision but minimal glandular removal
• 19325 (Breast augmentation with implant): augmentation counterpart; relevant in combined reduction-augmentation planning
• 19350 (Nipple/areola reconstruction): may be separately reportable when free nipple graft technique is used during 19318
• 19380 (Revision of reconstructed breast): CPT codebook explicitly prohibits reporting 19380 with 19318 for the same breast
• 15877 (Suction assisted lipectomy, trunk): potential add-on for separately documented axillary liposuction at same session; NCCI verification required
• N62 (Hypertrophy of breast): primary diagnosis for symptomatic macromastia; covers all hypertrophy subtypes
• N65.1 (Disproportion of reconstructed breast): primary diagnosis for symmetry reduction after mastectomy reconstruction; key to Medicare WHCRA coverage
• M54.2 (Cervicalgia): secondary diagnosis supporting functional medical necessity

Sources

1. CPT 19318 database record, case2code CPT database — code attributes, payment indicators (bilateral indicator, MUE, global days, assistant surgeon, co-surgeon, team surgery indicators), code history (changed 2021-01-01)
2. ICD-10-CM N62, N65.1, M54.2, M54.59, L30.4 database records, case2code ICD-10-CM database — diagnosis code descriptions and code relationships
3. CPT 19316, 19325, 19350, 19380, 15877 database records, case2code CPT database — related code descriptions and CPT codebook cross-references
4. CPT codebook guidelines for 19318 (via database record) — codebook instructions on 19380, 19316, 19318 reporting relationships and mastectomy procedure direction