Sleep apnea is a common and potentially serious condition in which breathing repeatedly stops and starts during sleep. Left untreated, it can contribute to high blood pressure, heart disease, stroke, and daytime fatigue that affects every aspect of your life. The most widely prescribed treatment is a CPAP (Continuous Positive Airway Pressure) machine, and Medicare does cover it — but with specific requirements you need to understand before you get started.
How Medicare Covers CPAP Machines Under Part B
Medicare Part B classifies CPAP machines as durable medical equipment (DME). Coverage is available when all of the following conditions are met:
- You have been diagnosed with obstructive sleep apnea through a qualifying sleep study
- Your treating physician prescribes CPAP therapy as medically necessary
- You obtain the equipment from a Medicare-enrolled DME supplier
When these criteria are satisfied, Medicare pays 80 percent of the approved rental amount, and you pay the remaining 20 percent coinsurance after meeting your annual Part B deductible. For more on how copays and coinsurance work in Medicare, see our comparison guide.
It is important to note that Medicare does not purchase CPAP equipment for you outright at the start. Instead, it follows a rental-to-own model.
The 13-Month Rental-to-Own Process
Medicare's approach to CPAP coverage operates on a 13-month rental timeline:
- Months 1 through 3: This is the initial trial period. Medicare rents the CPAP machine on a month-to-month basis while you demonstrate that you are using the device consistently and benefiting from the therapy.
- Month 4 reassessment: After three months of use, your doctor must conduct a follow-up evaluation. If the physician confirms that CPAP therapy is working and should continue, the rental extends.
- Months 4 through 13: If approved to continue, you keep renting the machine. Medicare continues paying 80 percent of the monthly rental cost.
- After month 13: Once you have completed 13 months of rental payments, you own the machine. No further rental charges apply, and the equipment is yours to keep.
If your doctor determines during the initial three-month trial that CPAP is not effective or that you are not using it, Medicare will stop paying for the rental. You would then need to return the equipment to the supplier.
Compliance and Usage Tracking Requirements
This is where many beneficiaries run into trouble. Medicare imposes strict compliance requirements during the initial trial period to verify that you are actually using the CPAP machine. Specifically:
- You must use your CPAP device for at least 4 hours per night
- This usage must occur on at least 70 percent of nights during a consecutive 30-day period
- The 30-day compliance window must fall within the first 90 days of receiving the device
Modern CPAP machines have built-in data tracking that records your nightly usage hours. Your DME supplier or physician will download this data to document your compliance. If you do not meet the minimum usage threshold, Medicare may deny continued coverage, and you could be responsible for returning the machine or paying for it out of pocket. If your coverage is denied, you have the right to appeal the decision.
Tips for meeting compliance requirements:
- Use the device every night from the moment you receive it — do not wait to "get used to it"
- If the mask is uncomfortable, contact your supplier immediately for a different size or style
- Set a nightly routine that includes putting on your CPAP before you fall asleep
- Track your own usage through the machine's companion app, if available
Sleep Study Coverage
Before Medicare will approve CPAP therapy, you need a confirmed diagnosis of obstructive sleep apnea. Medicare covers two types of sleep studies:
Facility-Based Sleep Study (Polysomnography)
A polysomnography (PSG) is an overnight study conducted in a certified sleep laboratory. Technicians monitor your brain activity, eye movements, heart rate, oxygen levels, breathing patterns, and muscle activity while you sleep. Medicare Part B covers this study with standard cost-sharing:
- You pay 20 percent coinsurance after meeting your Part B deductible
- The study must be performed at a Medicare-approved sleep facility
Home Sleep Apnea Test (HSAT)
Medicare also covers home sleep apnea testing, which allows you to take a portable monitoring device home and record your sleep data overnight. An HSAT is less comprehensive than an in-lab study but is often sufficient for diagnosing moderate to severe obstructive sleep apnea.
- Home tests are generally less expensive and more convenient
- Your doctor must order the test and interpret the results
- Standard Part B cost-sharing applies
If a home test produces inconclusive results, your doctor may refer you for a full in-lab polysomnography.
Replacement Schedules for CPAP Supplies
Once you own your CPAP machine, you will still need ongoing supplies. Medicare covers replacement supplies on a set schedule. Here are the general replacement intervals:
- CPAP filters: Disposable filters every 2 weeks; reusable filters every 6 months
- Mask cushions or nasal pillows: Every 1 to 3 months, depending on the type
- Full mask or headgear: Every 3 months for cushions, every 6 months for the complete mask assembly
- CPAP tubing: Every 3 months
- Humidifier water chamber: Every 6 months
- CPAP machine replacement: Every 5 years, if the existing machine is no longer functioning properly and cannot be repaired
To receive replacement supplies through Medicare:
- You must continue to have a valid prescription for CPAP therapy
- Supplies must be obtained from a Medicare-enrolled DME supplier
- Standard 20 percent coinsurance applies to each supply order
Medicare Advantage and CPAP Coverage
If you are enrolled in a Medicare Advantage (Part C) plan, your CPAP benefits must be at least as comprehensive as Original Medicare's coverage. However, your plan may impose different rules, such as:
- Network restrictions — you may need to use a specific DME supplier within the plan's network
- Different copay or coinsurance amounts
- Prior authorization requirements before receiving equipment or supplies
Check your plan's Evidence of Coverage document or call the plan directly to understand the specific steps required.
Making the Most of Your CPAP Benefits
- Choose a reliable DME supplier that is enrolled in Medicare and experienced with CPAP equipment. A good supplier will help you select the right mask, troubleshoot fit issues, and manage your supply reorders.
- Keep all follow-up appointments with your doctor. The month-4 reassessment is mandatory for continued coverage.
- Do not ignore compliance tracking. Those first 90 days are the most critical window for maintaining your Medicare benefit.
- Order replacement supplies on schedule. Worn-out masks and filters reduce the effectiveness of your therapy and can lead to air leaks, discomfort, and lower compliance.
- Review your Medicare Summary Notices to confirm that supply orders are being billed correctly and that you are not being overcharged.
The Bottom Line
Medicare provides meaningful coverage for CPAP machines and sleep apnea treatment, but the process requires you to play an active role. Meeting compliance thresholds, keeping follow-up appointments, and ordering supplies on schedule will help ensure uninterrupted therapy — and better sleep — for years to come.