Original MedicareOriginal Medicare is a fee-for-service health insurance program available to Americans aged 65 and older and some individuals with disabilities. Original Medicare is provided by the federal government and is made up of two parts: Part A (hospital insurance) and Part B (medical insurance). will cover at least a portion of your visit to the emergency room.
The part of Medicare that covers your visit will depend on if you are admitted or not.
If you are admitted to the hospital for at least two nights after an ER visit, Medicare Part A covers it.
If you are not admitted after an ER visit, Medicare Part B will cover it.
Original Medicare will cover a portion of your visits to the emergency room, but whether or not you are admitted will determine if Part A or Part B coverage is used. In either case, you pay a portion of your cost for services, but Medicare pays the majority.
If you have a Medicare Advantage plan, your ER visit will be covered and the plan you choose will determine your out-of-pocket costs. You may also have to pay more for visiting doctors or facilities that are outside your plan’s network.
Does Medicare Part A and B cover emergency room visits?
Both Medicare Part A and B offer some coverage of emergency services depending on how long you need to stay in the hospital. If your ER visit leads to a hospital stay, Medicare Part A covers the costs, plus any services that were provided in the three days before your admission. If your visit is one where you are discharged from the emergency room or after just one night of observation, Medicare Part B will provide coverage.
Will Medicare Part A cover emergency room visits?
Medicare Part A only covers emergency room services when you are admitted by a doctor for at least two nights in the hospital. The “Two-Midnight” rule is important, because in some cases your doctor may just keep you one night for observation. These visits are considered outpatient care even though you spent the night in the hospital, and Medicare Part B will provide coverage. 
Medicare Part B covers most emergency visits, especially if you are seen and sent home the same day, or spend one night for observation. Even if you are admitted, Part B will pay the portion of your bill that covers doctor’s services while Part A will pay inpatient hospital costs.
Original Medicare does not have an established copay for emergency room visits. Instead, you will pay a share of the costs based on your Part A or Part B coverage, and which part of Medicare is applied to your visit.
If you are admitted for at least two nights after and ER visit and Part A is used, you will pay: 
- A $1,484 deductible for each inpatient stay for each benefit period. Benefit periods reset every 60 days you spend outside of a hospital or skilled nursing facility.
- If you were recently admitted and already paid this deductible for your benefit period, you will not have to pay it again for the same benefit period.
- Coinsurance applies, also, but only after 60 days of hospitalization.
If you visit the emergency room and are sent home right away or are admitted for just one night of observation, Part B coverage applies. This will cost you:
- Your annual deductible — $203 for 2021 — if you haven’t already met it for the year.
- Twenty percent of the remainder of the Medicare-approved costs associated with the visit.
How much of a hospital bill does Medicare pay?
When Medicare Part A is applied for emergency department visits that turn into an inpatient stay, your costs will be covered after you pay your deductible and coinsurance.
When Medicare Part B is used for an ER visit where you are not admitted or kept only one night for observation, Medicare pays for 80% of the approved cost after your deductible is met.
Can I get help paying?
If you need help paying for your share of your emergency department bill — regardless of whether Medicare Part A or B was applied — you may be able to use additional coverage if you’ve signed up for a Medicare supplement plan. Medicare supplement plans can only be purchased if you have Original Medicare (Parts A and B). If you have a Medicare Advantage plan, you will need to leave that policy.
Costs of Medicare supplement plans vary based on which plan you choose. Medicare supplement plans can be used to cover costs such as deductibles, copayments and coinsurance that are not covered by Original Medicare.
There is no limit to how many ER visits Medicare covers, but you may have to start a new benefit period if it’s been awhile since your last admission. If you are admitted to the hospital and it’s been more than 60 days since your last admission, you will have to start a new benefit period and pay your Part A deductible. If you were admitted within the last 60 days, you will not have to pay this deductible again since you are in the same benefit period.
Regardless of whether you are admitted or not following an ER visit, Medicare Part B is used to pay for ambulance services. If you’ve already met your Part B deductible for the year, you will be responsible for 20% of the cost of these services.
Medications that you are given while admitted in the hospital are covered under Part A. If you are given a prescription in the emergency room and sent home, you will have to pay for this medication unless you have Medicare Part D coverage (prescription drug plans). Costs for prescription coverage vary based on the Medicare Part D plan you choose.