CPT Code 21320: Closed treatment of nasal bone fracture with stabilization

Key takeaways

CPT Code 21320 describes closed treatment of a nasal bone fracture with stabilization, such as an external splint or internal packing. No surgical incision is made.

Documentation has to name the stabilization method used. That is what separates 21320 from CPT 21315, which covers the same fracture without stabilization.

The most common denial trigger is billing 21315 when stabilization was performed but never written down. Modifier errors run a close second.

Medicare pays roughly $220 in the office and $82 in a facility in 2026, before any locality adjustment.

CMS assigns 21320 a 000 global period, so follow-up visits after the day of the procedure are separately billable.

Practice management software like Pabau tracks each 21320 claim from submission to payment. Its note templates capture the stabilization method at the point of care.

CPT Code 21320: Definition and clinical description

CPT Code 21320 covers closed treatment of nasal bone fracture with stabilization. The physician reduces and manipulates the fractured nasal bones without making a surgical incision. The reduction is then held in place with an external nasal splint, internal packing, or both. Codes 21325 and 21330 cover the same injury treated through an open approach.

The American Medical Association (AMA) maintains the CPT code set and lists 21320 under fracture and dislocation procedures on the head. Anesthesia varies with the case. Local anesthesia, procedural sedation, and general anesthesia are all used, depending on patient cooperation and the degree of displacement. ENT surgeons, plastic surgeons, and emergency physicians bill this code most often.

Practices that see facial trauma regularly, including plastic surgery practices, configure their documentation templates in advance. The stabilization method, anesthesia type, and imaging confirmation then get captured at the point of care every time.

How 21320 differs from 21315, 21325, and 21330

The nasal fracture CPT code family covers four distinct clinical scenarios. Selecting the wrong code is the leading denial reason for this procedure. The key differentiators are whether treatment is open or closed, and whether stabilization was applied.

The 21315 versus 21320 distinction is the one that costs money. Both cover closed treatment of the same fracture, and the only difference is the stabilization applied at the end. Payers audit that difference closely.

If the procedure note does not name the stabilization method, the claim defaults to 21315 on review. Document the method in plain words, such as “dorsal nasal splint applied” or “anterior nasal packing placed.”

Related injuries have their own codes. An open septal repair performed alongside the nasal fracture is reported with 21335. Open treatment of the septum by itself is 21336, and a complicated frontal sinus fracture is 21344.

CPT Code 21320 reimbursement rates and the 2026 Medicare fee schedule

Reimbursement for CPT Code 21320 varies by setting, geographic locality, and payer. Medicare rates are published annually by CMS and differ between facility settings, such as a hospital or ASC, and non-facility office settings. Verify current figures with the CMS fee schedule tool before quoting rates to patients.

The figures below are 2026 national amounts, calculated from the published relative value units and the conversion factor. Your locality-adjusted rate will differ, because the geographic practice cost index applies to each component. Commercial payers may reimburse at multiples of Medicare, depending on the contract.

Both amounts are national averages before any locality adjustment. Check your own allowable through payer portals or the CMS look-up tool before you bill or quote a self-pay price.

RVU values and payment calculation

Relative value units (RVUs) are the basis of every Medicare payment calculation. Add the work, practice expense, and malpractice RVUs, then multiply the total by the conversion factor. For 2026 that factor is $33.40, or $33.57 for clinicians in a qualifying alternative payment model. The values below come from the 2026 CMS relative value files.

That puts the office total at 6.61 RVUs and the facility total at 2.45. Note how much of the office payment sits in practice expense, since the splint, packing, and staff time are all supplied by the practice. CMS updates both the RVUs and the conversion factor each January, so re-check them before contract talks.

Which modifiers apply to CPT 21320

Modifier selection directly affects payment and payer edit outcomes. The modifiers below are the ones that come up on nasal fracture claims, though applicability varies by payer and by clinical circumstance. Verify against National Correct Coding Initiative (NCCI) edits and your payer contracts before appending any modifier.

Modifier decisions still come down to the coder and the NCCI tables. Check the quarterly edit files for 21320 before you append -59, then keep a note of the pairing you relied on. That record is what supports the claim if the payer comes back.

ICD-10 diagnosis codes to pair with 21320

Every CPT claim needs a supporting ICD-10-CM diagnosis code to establish medical necessity. For nasal bone fracture treatment, coders select the code by fracture type and by the phase of care at that visit. The codes below are the ones most frequently paired with CPT Code 21320.

The 7th character carries the weight here. Using S02.2XXA at a follow-up visit, where D belongs, is a common error that invites payer audits. The character has to match the phase of treatment at that visit, not the date of injury.

The same logic runs across the neighboring facial fracture codes, including S02.81XG. Check that every code you use is active for the fiscal year with the CDC ICD-10-CM tool.

Emergency departments, sports medicine practices, and ENT practices see most of these injuries. Building the pairing rules into digital intake forms prompts the right 7th character during the encounter, rather than after a denial.

Global period and post-op billing

CMS assigns CPT Code 21320 a 000 global period, which means zero post-operative days. Only the work on the day of the procedure is bundled into the payment. A splint check the following week is a separately billable visit, not bundled aftercare.

• Day of the procedure: Pre-operative and post-operative work on that date is included in the 21320 payment.
• A separate visit on the same day: Bill an E/M only where the visit was significant and separately identifiable. Append modifier -25 to the E/M code.
• The day after and beyond: No post-operative window applies, so healing checks and packing removal can be billed as visits when documented.
• Post-operative modifiers: Modifiers -24, -58, -78, and -79 all describe work inside a global window, so they have no role on a 000 code.
• Repeat treatment: If the fracture needs re-reduction, bill the procedure again with modifier -76 and a note explaining the second treatment.

Confirm the global indicator in the current MPFS file before you set billing policy, since indicators do change between years. Practices opening a cosmetic surgery practice should check the indicator for every surgical code they plan to bill. A 010 or 090 code is handled very differently from this one.

Documentation requirements for a clean 21320 claim

Incomplete documentation is the second most common denial cause for CPT Code 21320, after wrong code selection. The procedure note has to carry all of the elements below to support medical necessity and hold the claim at 21320 rather than 21315.

• Imaging confirmation: Plain radiograph or CT scan confirming nasal bone fracture with displacement or significant deformity warranting treatment.
• Physical examination findings: Nasal deformity, tenderness, crepitus, or septal deviation documented in the visit note before the procedure.
• Anesthesia type: Specify whether local, procedural sedation, or general anesthesia was used. This supports the complexity level of the service.
• Method of reduction: Document the closed reduction technique used, whether instrument or digital manipulation.
• Stabilization method: Name what was applied, such as an external dorsal nasal splint, a foam or Aquaplast splint, or anterior or posterior nasal packing. The phrase stabilization applied is not enough on its own.
• Time from injury: Nasal fractures are generally treated within 7-10 days of injury, while soft tissue swelling still allows manipulation. Document the injury date and the treatment timing.
• Medical necessity statement: A sentence connecting the clinical findings to the treatment decision, particularly if the fracture does not appear severely displaced.

Capturing these elements in structured medical forms cuts down on retrospective record requests from payers. A checklist-style procedure note also helps junior staff capture the stabilization detail. That one line is the difference between a 21320 and a 21315 claim.

Common billing errors and denial reasons

Most CPT 21320 denials fall into a short list of preventable categories. Recognizing them in advance is significantly cheaper than working remittance advice and appeals after the fact.

• Coding 21315 when stabilization was performed: The most expensive miss in this code family. If your stabilization rate is high and your 21315 volume is too, review the procedure notes for missing language.
• Generic stabilization documentation: A note saying stabilization was performed, without naming the method, gives reviewers room to downcode to 21315. Always name the device or technique.
• Wrong ICD-10 7th character: Using the initial encounter suffix on a follow-up visit triggers medical necessity edits. Match the 7th character to the phase of care at each encounter.
• Treating 21320 as though it had a post-op window: Follow-up visits after the day of the procedure are billable on a 000 code. Writing them off as bundled leaves money uncollected.
• Modifier -51 missing on same-day procedures: If 21320 is performed alongside a higher-RVU procedure on the same date, modifier -51 belongs on 21320. Leaving it off can trigger a bundling denial.
• Lack of prior authorization: Many commercial plans require prior authorization for surgical fracture treatment. Verify the requirement before the procedure, not after.

A plastic surgery practice EMR is built to hold this kind of surgical coding detail. Structured notes and a review before submission carry across every surgical code family.

How practice management software supports 21320 billing

Most 21320 denials start in the workflow rather than the treatment room. A procedure note goes out without the stabilization method named. A claim sits unsubmitted for three weeks. An insurer detail is missing, so the payer rejects the whole thing and nobody notices until the month-end report.

Practice management software like Pabau closes those loops earlier. Purpose-built plastic surgery software keeps the clinical note, the claim, and the payment record in one system, so nothing has to be reconstructed weeks later.

• Structured note templates: A nasal fracture template with required fields for stabilization, anesthesia, and imaging keeps the note complete at the point of care.
• Claims submitted and tracked in one place: Pabau’s claims management software submits each claim and follows it through to payment. A rejection surfaces in days.
• Missing insurer details caught early: It flags an incomplete insurer or policy record before the claim goes out. That removes one routine rejection reason.
• Follow-up visits on the record: Appointments link back to the procedure record. Your billing team can see which visits followed the treatment and code each one on its merits.
• Payments reconciled against the claim: Remittances line up against what was submitted. A downcoded 21320 shows up instead of hiding in an unreconciled balance.

A coding reference tells you what the rules are. The workflow is what makes those rules stick on a busy Tuesday. Practices juggling facial trauma volume and HIPAA compliance get more out of the second than the first.

Track every surgical claim through to payment

Pabau keeps the procedure note, the claim, and the payment in one system. Your team can see where every 21320 claim sits without chasing a spreadsheet.

Book a demo

Conclusion

CPT Code 21320 is simple in concept and leaky in practice. Two words in the procedure note, with stabilization, decide whether the claim pays at 21320 or drops to 21315 on review.

So the fix sits upstream of billing. Change the note template first, then check your 21320 to 21315 ratio next quarter to see whether it took. The 000 global period is the second thing worth acting on, because every follow-up visit you wrote off as bundled was billable.

Neither change needs new software. Both are easier to hold in place when the note, the claim, and the payment live in one system. Book a demo to see how Pabau handles surgical claims for ENT and plastic surgery practices.

Continue your research

Treating a midface fracture alongside the nasal bones? CPT Code 21348 covers open treatment of a nasomaxillary complex fracture and the documentation it needs.

Coding an orbital floor fracture from the same injury? ICD-10 Code S02.121B walks through laterality and the 7th character rules for orbital fractures.

Another surgical code with strict staging rules? CPT Code 17312 shows how add-on stage billing works for Mohs surgery.

Want a CPT workflow worked through end to end? Coaching CPT codes applies the same documentation and modifier discipline to a very different service.

Wondering which software features cut billing admin the most? Practice management software features maps the tools that connect clinical notes to submitted claims.

Frequently asked questions