HCPCS code A4615 – Nasal cannula

Key takeaways

HCPCS code A4615 is the code for a nasal cannula, the two-pronged device that delivers oxygen through the nostrils. Its official descriptor is “Cannula, nasal”.

Medicare includes A4615 in the monthly rental for oxygen equipment under LCD L33797, so a supplier does not bill it as a separate line.

Oxygen tubing has its own code, A4616, billed per foot. Mixing up the two codes is a common coding error.

CMS retired the oxygen CMN (CMS-484) for dates of service from January 1, 2023. Documentation now rests on the order, the qualifying test, medical records and proof of delivery.

Pabau, the billing and practice management platform we build, helps DMEPOS suppliers keep oxygen documentation together and review it before a claim goes out.

What HCPCS code A4615 covers

HCPCS code A4615 covers a nasal cannula, the lightweight two-pronged device that sits in the nostrils and delivers oxygen from a home oxygen system. Its official descriptor is “Cannula, nasal”. One unit on the claim equals one cannula.

A4615 sits in the A4611-A4629 range of respiratory supplies, part of the HCPCS Level II codes for medical supplies. Its neighbors are A4616 for oxygen tubing and A4617 for a mouthpiece.

For Medicare, the cannula is an oxygen accessory rather than a standalone supply. The Oxygen and Oxygen Equipment LCD (L33797) and its policy article A52514 list cannulas among the accessories included in the allowance for rented oxygen equipment.

What A4615 does not cover

• Oxygen tubing, which is billed per foot under A4616
• Mouthpieces, which have their own code, A4617
• Masks, face tents and other delivery devices, which each carry their own A-code
• Oxygen equipment such as concentrators and portable systems, billed under E-codes such as E1390 and E0431

Code descriptor and key facts at a glance

The table below summarizes the core billing facts for A4615, drawn from the CMS HCPCS Level II code set. Check the current CMS annual release before you submit claims.

A4615 vs. A4616: Nasal cannula or per-foot tubing

A4615 and A4616 are often confused because both items sit on the same oxygen setup. A4615 is the nasal cannula, the part that touches the patient. A4616 is the oxygen tubing that connects the cannula to the oxygen source, billed per foot.

Code the item that was dispensed. A cannula is A4615, and extension tubing is A4616, reported in feet. On a Medicare oxygen rental neither code is paid as a separate line. The choice matters most for Medicaid, commercial payers and inventory records.

Related and commonly confused codes

Oxygen accessories span several HCPCS codes. The table below shows the codes most often billed alongside or instead of A4615, and when each one applies.

Medicare billing requirements for HCPCS code A4615

Medicare does not pay A4615 as its own line when the cannula supports rented oxygen equipment. The Oxygen LCD (L33797) and policy article A52514 include cannulas in the monthly rental allowance for that equipment. The supplier furnishes the cannula as part of the rental and bills only the equipment code, such as E1390 for a stationary concentrator.

That duty continues past the 36-month rental cap. The supplier who billed month 36 must keep furnishing accessories through the five-year reasonable useful lifetime, with no separate payment. On beneficiary-owned equipment, Medicare treats accessories as statutorily non-covered.

The oxygen rental that covers the cannula still has to meet the LCD. These are the core requirements.

• Qualifying blood gas study: An arterial PaO2 or oxygen saturation (SpO2) result that meets the LCD criteria. A qualified provider performs the test, not the DME supplier.
• Standard written order: A valid order from the treating practitioner, on file before the supplier submits the claim.
• Medical records: The treating practitioner’s notes, showing the condition that oxygen treats.
• Proof of delivery: A signed, dated delivery record for the equipment and its supplies.
• Supplier enrollment: Active Medicare DMEPOS enrollment and accreditation from a CMS-approved organization.

CMS retired the oxygen Certificate of Medical Necessity (CMS-484) for dates of service on or after January 1, 2023. CGS, a DME MAC, confirms that claims arriving with a CMN or DIF attached are now rejected. The medical record carries that evidence instead, and keeping it in order is part of DMEPOS billing compliance.

Required documentation

Suppliers must keep the following records on file and produce them when the DME MAC or an auditor asks. A missing record can turn a paid oxygen rental, including its cannulas, into an overpayment on review.

• Standard written order from the treating practitioner, showing the order date and the items ordered
• Qualifying blood gas results (PaO2 or SpO2) that meet the LCD criteria and timing
• Medical records supporting the condition oxygen treats and the treating practitioner’s evaluation
• Proof of delivery for the equipment and each cannula supplied, signed and dated
• The supplier’s DMEPOS accreditation certificate and Medicare enrollment records
• Any further oxygen documentation your DME MAC’s policy article lists

Modifiers used with A4615

Modifier use for A4615 follows your DME MAC’s oxygen LCD and policy article, not a fixed list. Because Medicare includes the cannula in the rental payment, oxygen modifiers usually belong on the equipment line rather than on A4615.

The N1, N2 and N3 group modifiers are one example. Since April 1, 2023, the policy article requires one of them on initial oxygen equipment claims. When Medicaid or a commercial plan pays A4615 separately, follow that payer’s own modifier rules.

Payment and reimbursement for A4615

Medicare Part B does not pay A4615 separately for rented oxygen, so there is no standalone Medicare allowable to bill the cannula against. Payment reaches the supplier through the monthly rental for the oxygen equipment code. Knowing the medical billing fundamentals behind fee schedules helps billing teams model that bundled revenue correctly.

The rental allowances themselves sit in the CMS DMEPOS fee schedule, which CMS updates each year by locality. Other payers handle the cannula in their own way, and the diagram below shows where a separate A4615 line can and cannot go.

• Medicaid: State Medicaid programs may pay A4615 separately, with their own coverage criteria, quantity limits and rates. Check your state’s DMEPOS fee schedule.
• Commercial payers: Private plans set their own bundling rules. Confirm in the payer contract whether cannulas are paid separately or included in the oxygen rental.

Common denial reasons and how to avoid them

Most A4615 denials come from treating the cannula as a separately payable item. The denial management strategies that work here focus on bundling rules, LCD documentation and code selection.

How to appeal a denied A4615 claim

Medicare offers a five-level appeals process, but an appeal helps only when the denial came from a documentation or coding error. A bundling denial on a rented oxygen system reflects payment policy, so appealing it rarely changes the outcome.

A habit of clean claim submission keeps those lines off the claim to begin with. When an appeal is justified, the steps below apply.

1. Redetermination (Level 1): Submit a written redetermination request to the MAC within 120 days of the initial determination. Include the remittance advice, the standard written order, the qualifying test results, proof of delivery and any record that answers the denial reason. The MAC generally decides within 60 days.
2. Reconsideration (Level 2): If the MAC upholds the denial, request reconsideration from the Qualified Independent Contractor (QIC) within 180 days of the redetermination notice. Explain in writing why the coverage criteria were met, quoting the specific LCD language.
3. ALJ hearing (Level 3): Request an Administrative Law Judge hearing within 60 days of the QIC decision. The amount in controversy must meet a threshold that CMS adjusts each year.
4. Medicare Appeals Council (Level 4) and federal court (Level 5): Medicare Appeals Council (Level 4) review is available after an ALJ decision. Federal court (Level 5) requires the amount in controversy to meet a threshold CMS sets each year.

Strong appeals cite the exact LCD criterion met and attach the qualifying test results and the treating practitioner’s records. Generic appeal letters without specific LCD references rarely succeed.

How Pabau helps DMEPOS suppliers bill oxygen accessories

Many oxygen suppliers still track orders, test results and delivery records across spreadsheets, email and paper files. A bundled cannula line or a missing delivery record then surfaces only when the denial arrives.

Pabau keeps the order, the test results and the delivery record with each patient. Billing teams can review the documentation before a claim goes out and follow each claim through to payment. The result is fewer avoidable denials and less rework for your billing team.

Simplify DMEPOS billing documentation with Pabau

Pabau’s claims management workflows help DMEPOS suppliers and medical billers keep orders, test results and delivery records together, so oxygen claims go out clean.

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Conclusion

Treat A4615 as a Medicaid and commercial code first. On a Medicare oxygen rental, the cannula is already paid inside the monthly equipment payment, so a separate line only earns a denial.

Your billing effort pays off in the documentation instead. A complete order, qualifying test and delivery record protect the whole rental, cannulas included, when an auditor asks. Coding the cannula, tubing or mouthpiece by the item dispensed keeps Medicaid claims and inventory counts accurate.

Pabau’s claims management workflows give DMEPOS billing teams a structured way to keep oxygen documentation together and reduce the rework that denied claims create. Book a demo to see how Pabau keeps oxygen documentation ready before each claim goes out.

Continue your research

Need a deeper overview of how DMEPOS billing fits into the wider revenue cycle? What is revenue cycle management covers the end-to-end process from eligibility verification through payment posting.

Want to understand how clearinghouses process DMEPOS claims electronically? Medical claims clearinghouse guide explains how claims move from the supplier’s billing system to the MAC.

Looking for practical steps to reduce claim rejection rates across your practice? Superbill documentation guide walks through the documentation elements that support clean claim submission.

Dispensing a mouthpiece instead of a nasal cannula? HCPCS code A4617 covers the descriptor and Medicare rules for oxygen mouthpieces.

Supplying a home fill system for portable cylinders? HCPCS code K0738 explains how that oxygen equipment rental is billed.

Frequently asked questions