With Original Medicare, you’ll typically pay 20% of the Medicare-approved amount for a CPAP machine after meeting your Part B deductible. The machine is rented rather than purchased outright, so your out-of-pocket costs are spread across monthly payments. For most people, that works out to roughly $30 to $60 per month for the machine rental, plus smaller amounts for supplies like masks and tubing.
How Medicare Covers CPAP Equipment
CPAP machines fall under Medicare Part B as durable medical equipment (DME). Medicare doesn’t buy the machine for you. Instead, it pays 80% of the approved rental amount each month, and you cover the remaining 20% coinsurance. This only kicks in after you’ve met your annual Part B deductible, which is $257 in 2025.
The Medicare-approved amount for a standard CPAP device (billing code E0601) varies slightly by region but generally falls in the range of $80 to $120 per month. Your 20% share of that is relatively modest. Medicare also covers related supplies, including masks, tubing, filters, and water chambers, at the same 80/20 split. These supply costs add another $10 to $30 per month depending on which items you’re replacing and how often.
The Rental-to-Ownership Timeline
Medicare treats CPAP as a rental for 13 continuous months. During that period, you make monthly coinsurance payments. After 13 months of rental, ownership of the machine transfers to you at no additional cost. Once you own it, you stop paying for the machine itself, but Medicare continues covering replacement supplies.
This means your total out-of-pocket cost for the machine over the full rental period is roughly $200 to $400, assuming your supplier accepts Medicare assignment. After that, your ongoing expense is limited to supplies.
What “Accepting Assignment” Means for Your Bill
Your costs depend heavily on whether your DME supplier participates in Medicare and accepts assignment. A supplier that accepts assignment agrees to charge you only the 20% coinsurance and deductible based on the Medicare-approved rate. They can’t bill you above that amount.
If a supplier doesn’t participate in Medicare or refuses assignment, you could be charged significantly more. In that scenario, you may need to pay the full cost of the equipment upfront and then wait for Medicare to reimburse its share after your claim is processed. A CPAP machine purchased at retail typically costs $500 to $1,000 or more, so using a non-participating supplier can create a much larger upfront expense. Always confirm that your supplier accepts assignment for all rental months before starting.
Qualifying for Coverage
Medicare won’t cover a CPAP machine without a documented diagnosis of obstructive sleep apnea from a qualifying sleep study. The diagnostic threshold is specific: your sleep study must show an Apnea-Hypopnea Index (AHI) of 15 or more events per hour with at least 30 total events. If your AHI falls between 5 and 14 events per hour (with at least 10 total events), you can still qualify, but you’ll also need documented symptoms such as excessive daytime sleepiness, mood changes, impaired thinking, insomnia, or a related condition like high blood pressure, heart disease, or a history of stroke.
The sleep study itself is a separate cost. Medicare covers both in-lab sleep studies and certain home sleep tests, again at the 80/20 split after your deductible.
The 90-Day Compliance Check
Medicare initially approves CPAP coverage for a 12-week trial period. During those first three months, you need to demonstrate that the therapy is working and that you’re actually using the machine. The widely applied standard, based on guidelines from the American Academy of Sleep Medicine, requires using the CPAP for at least 4 hours per night on at least 70% of nights.
Modern CPAP machines track your usage automatically, so your supplier and doctor will have the data. If you don’t meet the usage threshold during this trial period, Medicare can stop covering the equipment. You’d then be responsible for returning the machine or paying for it yourself. A follow-up visit with your prescribing doctor during this window is also required to confirm the treatment is benefiting you.
Ongoing Supply Costs After You Own the Machine
Once you own the CPAP after 13 months, the machine itself costs you nothing further. But masks, cushions, tubing, filters, and humidifier chambers all wear out and need regular replacement. Medicare continues covering these supplies at the standard 80/20 coinsurance rate. Replacement schedules vary by item: mask cushions can typically be replaced monthly, full masks every three months, tubing every three months, and filters monthly or as needed depending on the type.
In practice, most people spend $5 to $20 per month on supply coinsurance if they’re replacing items on the Medicare-allowed schedule. Your supplier will often contact you when you’re eligible for replacements.
Medicare Advantage Plans
If you have a Medicare Advantage plan (Part C) instead of Original Medicare, your CPAP coverage must be at least as comprehensive as Original Medicare, but the cost-sharing structure can differ. Some Advantage plans charge a flat copay per rental month rather than a percentage. Others may have different preferred supplier networks or require prior authorization before approving the equipment. Check your plan’s summary of benefits for the specific DME cost-sharing terms, since they vary widely between insurers and plan tiers.
Medigap and Additional Savings
If you have a Medigap (Medicare Supplement) policy alongside Original Medicare, it may cover some or all of your 20% coinsurance. Several popular Medigap plans, including Plan F and Plan G, pick up Part B coinsurance in full, which would reduce your CPAP costs to little or nothing beyond the premiums you already pay for the supplement plan. If you’re on a limited income, Medicare Savings Programs or Medicaid may also help cover coinsurance and deductible costs.