Original Medicare denied durable medical equipment (a CPAP, oxygen, or a wheelchair)? What the rule says and how to appeal.
Checked against the current rules on September 26, 2026.
A denial for durable medical equipment (a CPAP, oxygen, or a wheelchair) isn't the end of the story — Original Medicare has to follow specific coverage rules, and a denial that doesn't square with those rules is exactly the kind of appeal that tends to win.
Here's what the rule actually requires, what evidence usually turns a denial around, and the deadline you're working against.
What the rule requires
Coverage for durable medical equipment (a CPAP, oxygen, or a wheelchair) under Original Medicare is governed byDurable Medical Equipment - General andContinuous Positive Airway Pressure (CPAP) Therapy For Obstructive Sleep Apnea (OSA) andHome Use of Oxygen andPower Mobility Devices. Original Medicare generally cannot apply a stricter test than what these rules require.
Questions that decide it
Before you appeal, these are the facts that usually decide whether a denial like this holds up:
Was the specific test the equipment requires actually done — a sleep test for CPAP, a blood-gas or oximetry test for oxygen?
Did the ordering practitioner see the patient in person before ordering the equipment?
What a winning appeal has to show
An appeal that wins usually includes:
The actual sleep-test, blood-gas, or oximetry report with its specific numeric result — CPAP and oxygen coverage each turn on a specific numeric threshold (AHI/RDI for CPAP; a qualifying hypoxemia reading for oxygen) — the exact number is the whole question. (Your doctor's office provides this.)NCD 240.4
The physician's Standard Written Order for the equipment — DME coverage requires a valid, dated order from the treating practitioner naming the specific item. (Your doctor's office provides this.)
Your deadline to appeal
120 days from the date on the Medicare Summary Notice — 120 calendar days from when you receive it (42 CFR § 405.942(a)), with receipt presumed to be 5 days after the notice's own date unless shown otherwise.42 CFR 405.942
Your Medicare contractor itself then has its own clock to decide. 60 calendar days from when the MAC receives your timely request. Each time you submit new evidence after filing, that 60-day clock is extended by up to 14 more calendar days for that submission (42 CFR § 405.950(a), (b)(3)) — this can happen more than once.
What to ask your doctor to address
If you're asking the treating physician for a supporting letter, it should speak to:
Whether the specific test result and clinical findings meet the named NCD/LCD's own numeric and documentation criteria.NCD 240.4
Questions people ask
- Can your Medicare contractor just say it's "not medically necessary" with no further explanation?
- The denial notice has to explain the basis for the decision and tell you how to appeal. If it doesn't point to a specific rule or criteria, that's itself worth raising in your appeal — you're entitled to know what standard was applied.
- What if I don't have all the evidence listed above?
- Include what you have. An appeal with partial evidence and a clear explanation of the rule still gets a real review — it doesn't need to be complete to be worth filing.
Sources — last checked September 26, 2026
- 42 CFR 405.942as of September 23, 2026
- Continuous Positive Airway Pressure (CPAP) Therapy For Obstructive Sleep Apnea (OSA)as of September 26, 2026
- Durable Medical Equipment - Generalas of April 1, 1987
- Home Use of Oxygenas of September 26, 2026
- Power Mobility Devicesas of October 1, 2025
Related
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By CaseWhy Appeals editorial. See how this content is produced. Not legal advice. Not affiliated with or endorsed by Medicare, CMS, or any health plan. A product of CaseWhy LLC.
