Medicare covers oxygen therapy for as long as your doctor prescribes it, with no built-in time limit
Medicare Part B pays for home oxygen equipment and supplies when a doctor orders them to treat a chronic lung condition. There is no maximum number of months Medicare will cover oxygen — the coverage continues month to month as long as your prescription remains active and your condition meets Medicare's medical necessity rules.
What changes over time is not whether Medicare pays, but what you pay out of pocket. After you meet your Part B deductible, you typically pay 20% of the approved amount for oxygen equipment and ongoing supplies. If you have a Medigap or Medicare Advantage plan, your out-of-pocket costs may be lower or structured differently.
Key Takeaways
- Medicare Part B covers home oxygen indefinitely as long as a doctor prescribes it and your oxygen level meets the threshold Medicare requires.
- Your doctor must order oxygen through a Medicare-approved supplier, and the supplier must submit paperwork showing your medical need before Medicare pays.
- You pay 20% of the Medicare-approved amount for oxygen equipment and supplies after you meet your annual Part B deductible.
- Medicare requires a new prescription and supporting test results every 12 months to keep paying for oxygen.
- If your oxygen needs change or your condition improves, your doctor can adjust or stop the prescription, and Medicare coverage will follow that change.
What Medicare requires to start paying for oxygen
Your doctor must order oxygen and document that you have a chronic lung condition — such as COPD, pulmonary fibrosis, or severe asthma — that causes your blood oxygen level to drop below a certain threshold. Medicare requires an oxygen saturation test (usually done with a pulse oximeter or arterial blood gas test) showing your oxygen level is 88% or lower at rest, during sleep, or during exercise.
The order must come from your doctor, and the oxygen must be supplied by a Medicare-approved durable medical equipment (DME) supplier. Your supplier handles the paperwork that goes to Medicare, including the prescription and test results. Medicare reviews this paperwork before it starts paying. If the paperwork is incomplete or does not show medical necessity, Medicare will deny the claim, and you may be billed for the equipment and supplies.
How much you pay each month
After you meet your Part B deductible for the year, you pay 20% of what Medicare approves for your oxygen. The exact amount depends on the type of equipment — a stationary concentrator costs differently than portable equipment or liquid oxygen — and how often you need refills or replacements.
For example, if Medicare approves $100 per month for your concentrator rental and supplies, you would pay $20 per month (20% of $100) after your deductible is met. If you have a Medigap plan, it may cover some or all of that 20%. If you have a Medicare Advantage plan, your costs depend on your plan's rules — some charge a copay per month, others charge a percentage, and some may have a maximum out-of-pocket limit.
Rental and purchase work differently under Medicare. Most people rent oxygen equipment through a DME supplier, and Medicare pays the supplier a monthly rental fee. If you buy equipment outright, Medicare pays a one-time purchase amount, and you own the equipment. Your doctor and supplier can discuss which option makes sense for your situation.
When Medicare stops paying for oxygen
Medicare stops paying when your doctor writes a new prescription ending oxygen therapy — usually because your condition has improved enough that you no longer need it, or because you have switched to a different treatment. Your doctor decides this based on your current oxygen levels and overall health.
Medicare also stops paying if you do not complete the required yearly recertification. Every 12 months, your doctor must order a new oxygen saturation test and write a new prescription. Your supplier submits this paperwork to Medicare. If this does not happen, Medicare will stop paying after your current prescription expires, even if you still need oxygen.
If you move to a nursing home or hospital, Medicare coverage for home oxygen pauses while you are in that facility. When you return home, your doctor can restart the prescription, and Medicare will resume paying.
Portable oxygen and travel
If you need oxygen while away from home, Medicare covers portable oxygen equipment — either a portable concentrator or liquid oxygen — as part of your overall oxygen prescription. Your supplier can provide portable equipment alongside your stationary concentrator at home. You still pay 20% of the approved amount for both.
Portable concentrators are battery-powered machines that let you move around your home and leave for appointments or outings. Liquid oxygen systems are lighter and smaller but require refills. Your doctor and supplier will recommend which type works best for how active you are and how long you are away from home at a time.
What to ask your doctor
Before your doctor writes an oxygen prescription, ask whether your recent test results show you meet Medicare's oxygen level threshold. Ask how long your doctor expects you to need oxygen — this helps you plan for equipment choices and understand what to watch for if your condition changes. Ask whether your doctor will handle the yearly recertification or whether you need to schedule a follow-up appointment to have it done.
If your oxygen needs change — you feel short of breath more often, or you feel better and need it less — tell your doctor right away. Your prescription can be adjusted, and Medicare will pay for the new amount.
Working with your DME supplier
Your Medicare-approved supplier is responsible for submitting the paperwork to Medicare and billing you for your 20% share. Before you choose a supplier, ask whether they are in-network with your Medicare Advantage plan (if you have one), because out-of-network suppliers may charge you more. Ask what happens if equipment breaks — most suppliers provide a loaner while repairs are made.
Ask your supplier to explain your monthly bill and what each charge covers. Some bills show equipment rental, some show supply refills, and some show both. If a charge seems wrong or you do not understand it, ask the supplier to explain before you pay.
Frequently Asked Questions
Does Medicare cover oxygen if I only need it at night?
Yes. Medicare covers oxygen prescribed for use during sleep if your oxygen level drops below the threshold while you sleep. Your doctor orders a sleep study or overnight oxygen saturation test to document this. Coverage works the same way — you pay 20% of the approved amount after your deductible.
What if my oxygen needs improve and I do not need it anymore?
Your doctor can write a new prescription ending oxygen therapy, and Medicare stops paying. You keep the equipment you own, but rental payments stop. If your condition worsens later and you need oxygen again, your doctor can restart a prescription and Medicare will cover it again.
Do I have to use a specific supplier, or can I choose?
You can choose any Medicare-approved DME supplier. If you have a Medicare Advantage plan, check whether your plan has preferred suppliers — using them may lower your costs. You can switch suppliers at any time if you are unhappy with service or pricing.
What happens to my oxygen coverage if I move to a different state?
Medicare coverage follows you across state lines. Your current prescription remains valid, but you will need to find a new Medicare-approved supplier in your new state. Contact your current supplier before you move to ask for a copy of your prescription and test results to give to your new supplier.
Will Medicare pay for a backup oxygen system if my main equipment breaks?
Medicare typically covers one oxygen system. If your equipment breaks, your supplier should provide a loaner while it is repaired. If you want a backup system for peace of mind, you would pay out of pocket for it. Talk to your supplier about rental or purchase costs for a second system.