Surgical · Other

Chin augmentation using grafted or implant material placed without bony osteotomy — the genioplasty code when the surgeon adds volume rather than repositions bone.

Verified May 8, 2026 · 6 sources ↓

Medicare: $715.45
Total RVUs: 21.42
Global, days: 90
Region: Other

Drawn from CMSAaomsAAPCNIH

Documentation requirements

What must appear in the operative or office note to support the claim.

Source · Editorial brief grounded in 6 cited references ↓

Specify graft or implant material used: autograft, allograft, or prosthetic (type and size)
Confirm no osteotomy was performed — operative note must distinguish augmentation-only from sliding genioplasty
State the indication explicitly: cosmetic, craniofacial deformity, microgenia with functional impairment, or obstructive sleep apnea
For sleep apnea indications, include reference to polysomnography results or sleep study findings in the clinical note
Document preoperative photographs and facial measurements supporting the surgical plan
Record the surgical approach (intraoral vs. submental incision) and implant placement site

Applicable modifiers

Modifiers commonly billed with this code.

Source · AMA CPT modifier descriptors · CMS NCCI Policy Manual

22 Increased complexity 51 Multiple procedures 52 Reduced services 58 Staged or related 78 Unplanned return — related 79 Unrelated during global 24 Unrelated E/M during global

What this code covers

Source · Editorial summary grounded in 6 cited references ↓

CPT 21120 covers augmentation genioplasty performed with autograft, allograft, or prosthetic implant material. The key distinction: no osteotomy is performed. The surgeon places graft or implant material to add chin projection or volume while leaving the underlying bone intact. Use 21121 or 21122 when a sliding osteotomy is performed, and 21123 when a sliding osteotomy is combined with interpositional bone graft.

Indications split between cosmetic and reconstructive. Medicare and most commercial payers treat cosmetic genioplasty as a non-covered benefit. Reconstructive coverage applies when documented medical necessity exists — most commonly microgenia causing functional impairment, craniofacial deformity, or obstructive sleep apnea. For sleep apnea cases, the clinical note must reference objective diagnostic findings such as a polysomnography report; a bare diagnosis code alone is not sufficient for coverage.

The 90-day global period applies. Any chin-related follow-up visit within 90 days is bundled unless the visit addresses a clearly unrelated problem — bill that with modifier 24. If hardware removal is planned at the time of augmentation, append modifier 58 when billing the removal procedure in the postoperative period. Preauthorization is routinely required; check payer policy before scheduling.

RVU & reimbursement

Component RVUs and Medicare national rate. Actual payment varies by GPCI locality.

Source · CMS Physician Fee Schedule, RVU26A · January 2026

Work RVU	4.97
Practice expense RVU	15.53
Malpractice RVU	0.92
Total RVU	21.42
Medicare national rate	$715.45
Global period	90 days

Payment by site of service

Medicare pays different rates by setting. HOPD typically pays substantially more than ASC for the same procedure.

Source · CMS OPPS Addendum B·ASC HCPCS payment rates·2026

Setting	Medicare rate (national)
Office (PFS non-facility) Procedure performed in physician's office	$715.45
HOPD (APC 5165) Hospital outpatient department	$6,048.05
ASC (PI G2) Ambulatory surgical center (freestanding)	$3,025.62

Common denial reasons

The recurring reasons claims for CPT 21120 get rejected.

Source · Editorial brief grounded in CMS NCCI edits, AAOS coding appeals, and cited references ↓

Payer determines procedure is cosmetic and contractually excluded from coverage without documented functional indication
Missing or inadequate sleep study documentation when obstructive sleep apnea is the stated diagnosis
Wrong code selection — osteotomy performed but 21120 billed instead of 21121, 21122, or 21123
Preauthorization not obtained prior to surgery — many payers require prior auth for all genioplasty codes
Grafted bone or implant not specified in the operative note, leaving the augmentation method ambiguous for audit review

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 6 cited references ↓

01What is the difference between 21120 and 21121?

21120 is augmentation only — graft or implant placed, no bone cut. 21121 requires a sliding osteotomy that repositions a single piece of chin bone. If your surgeon moved bone, 21120 is wrong regardless of whether graft material was also placed.

02Is 21120 covered by Medicare?

Not for cosmetic purposes. Medicare excludes procedures directed solely at improving appearance. Coverage applies when medical necessity is documented — microgenia causing functional impairment or obstructive sleep apnea are the most defensible indications. Submit with supporting clinical notes and, for sleep apnea, the polysomnography report.

03Do I need to separately code for the implant or graft material?

The graft work is bundled into 21120. You may separately bill for the prosthetic implant supply using an appropriate HCPCS code for the device, but the surgical work of obtaining and placing autograft is included. Verify payer policy on implant pass-through billing.

04Can 21120 be billed same-day with orthognathic surgery codes?

Yes, but append modifier 51 to the lower-value procedure. Confirm NCCI edits for the specific combination before billing. Some payer policies bundle genioplasty into a concurrent Le Fort or mandibular osteotomy claim and require documentation justifying separate billing.

05What modifier applies if the patient needs hardware removal during the 90-day global?

If hardware removal was planned at the time of the index procedure, use modifier 58 on the removal claim. If the removal is unplanned and related to a complication of 21120, use modifier 78. Do not use modifier 79 for a related return to the OR.

06How do I bill a post-op visit unrelated to the chin augmentation within the global period?

Append modifier 24 to the E/M code and document clearly in the note that the visit addresses a condition unrelated to the genioplasty. The problem must be distinct — not a complication or routine follow-up of 21120.

Sources & references

Editorial content was developed using the following public sources. Last verified May 8, 2026.

Mira AI Scribe

Mira's AI scribe captures the graft or implant type and size, confirms the absence of osteotomy in the operative dictation, records the clinical indication (cosmetic vs. reconstructive), and flags when a sleep study or functional impairment rationale is mentioned. This prevents the most common denial path for 21120 — a payer reclassifying the claim as cosmetic because the functional indication was documented only in a separate intake form rather than in the operative note itself.

See how Mira captures CPT 21120 documentation