Medicare covers MRI scans, but only when your doctor orders one for a medically necessary reason

Medicare Part B covers magnetic resonance imaging (MRI) as a diagnostic tool when a doctor believes it is medically necessary to diagnose or treat a condition. You do not pay the full cost yourself — Medicare pays its share, and you pay a copay or coinsurance. The catch is that "medically necessary" has a specific meaning in Medicare's rules, and not every MRI your doctor wants to order will be covered. Understanding what Medicare will and will not pay for can help you avoid surprise bills.

The coverage rules differ slightly depending on whether you have Original Medicare (Part A and Part B) or a Medicare Advantage plan. Both types cover MRI, but the out-of-pocket costs and approval processes can vary. Some MRIs require advance approval from Medicare before the scan happens; others do not. Knowing which category your scan falls into matters, because getting approval beforehand can prevent a claim denial later.

Key Takeaways

  • Medicare Part B covers MRI when a doctor orders it as medically necessary, and you pay a copay (usually $0 to $50) or 20% coinsurance after you meet your deductible.
  • Some MRIs require prior authorization from Medicare before the scan; your doctor's office should request this, and you can ask them whether your specific scan needs it.
  • Medicare does not cover MRI for screening purposes when you have no symptoms or diagnosed condition — only when there is a medical reason to investigate a problem.
  • If you have a Medicare Advantage plan, your copay and approval process may differ from Original Medicare, so check your plan documents or call your plan's customer service.
  • If Medicare denies your MRI claim, you have the right to appeal, and your doctor can provide medical records to support why the scan was necessary.

What Medicare Part B Covers for MRI

Original Medicare Part B covers MRI of the brain, spine, joints, abdomen, pelvis, and other body parts when a doctor orders it to diagnose or monitor a medical condition. Common reasons Medicare covers MRI include suspected stroke, spinal cord injury, torn ligaments, tumors, multiple sclerosis, and infections. The scan itself is covered at 80% after you meet your annual Part B deductible (which is $240 in 2024, though this amount can change yearly). You pay 20% coinsurance, which is your share of the Medicare-approved amount for the scan.

The facility where you have the MRI matters. If the scan happens at a hospital outpatient department, you may also owe a separate facility copay in addition to the imaging copay. If it happens at an independent imaging center, you typically owe only the imaging copay. Ask the facility in advance whether it is hospital-based or independent, because the bill structure is different.

Medicare does not cover the cost of contrast dye separately if it is injected during the MRI — that cost is bundled into the imaging charge. However, if you have a documented allergy to gadolinium (the contrast agent used in MRI), tell your doctor before the scan so they can order a different type of imaging or use alternative contrast.

When Prior Authorization Is Required

Some MRI scans require prior authorization — meaning Medicare or your doctor's office must get approval from Medicare before the scan happens. Your doctor's office is responsible for requesting this authorization, not you. However, you should ask your doctor's office whether your specific MRI needs authorization, because if they do not request it and the scan is denied, you could be stuck with the bill.

MRIs of the brain and spine are the most common scans that require prior authorization. Your doctor will submit medical records and the reason for the scan to Medicare's contractor in your state. Medicare typically responds within a few business days. If approved, the scan can proceed. If denied, your doctor can appeal or order a different type of imaging (such as a CT scan) instead.

If your doctor orders an MRI without getting prior authorization when it was required, and Medicare later denies the claim, you are not responsible for the bill — the provider is. However, this can delay your care, so it is worth confirming in advance that authorization has been requested.

MRI Scans Medicare Does Not Cover

Medicare does not cover MRI for screening when you have no symptoms or diagnosed condition. For example, if you want an MRI of your brain to check for disease even though you have no headaches, memory problems, or neurological symptoms, Medicare will not pay for it. This rule applies even if you are willing to pay out of pocket — Medicare straightforward will not cover preventive or screening MRI.

Medicare also does not cover MRI ordered for certain non-medical reasons, such as to document an injury for a legal case or workers' compensation claim (unless the injury itself is being treated medically). Additionally, some experimental uses of MRI or scans ordered to monitor a condition that is already well-controlled may be denied if Medicare determines they are not medically necessary.

If your doctor believes an MRI is necessary but Medicare denies it, your doctor can request a peer-to-peer review, in which a Medicare medical reviewer speaks directly with your doctor about why the scan is needed. This conversation sometimes results in approval when the initial denial was based on incomplete information.

Your Out-of-Pocket Costs for MRI

Under Original Medicare Part B, your cost for an MRI depends on whether you have met your annual deductible. In 2024, the Part B deductible is $240. Once you meet it, you pay 20% coinsurance of the Medicare-approved amount for the scan. The Medicare-approved amount varies by location and facility, but a typical brain or spine MRI costs between $1,000 and $3,000 total, meaning your 20% share could be $200 to $600.

If you have not met your deductible yet, you pay the full deductible amount first, then 20% coinsurance on anything above that. If you have a Medigap supplemental insurance plan, it may cover some or all of your coinsurance, depending on which Medigap plan you have. Check your Medigap documents or call your Medigap insurer to see what they cover for imaging.

If you have a Medicare Advantage plan instead of Original Medicare, your copay for MRI is set by your plan and is often lower than the 20% coinsurance under Original Medicare — sometimes $0 to $50. However, Medicare Advantage plans may have stricter prior authorization requirements or may require you to use in-network imaging centers. Check your plan documents or call your plan's customer service number to learn your specific copay and whether the facility you plan to use is in-network.

How to Confirm Coverage Before Your MRI

Before scheduling an MRI, ask your doctor's office to confirm with Medicare that the scan is covered. Your doctor's office can submit a coverage inquiry to Medicare's contractor in your state, and Medicare will respond in writing about whether the scan is covered and whether prior authorization is needed. This takes a few business days but prevents surprises later.

You can also call Medicare directly at 1-800-MEDICARE (1-800-633-4227) and provide your doctor's name, the type of MRI, and the reason for it. Medicare staff can tell you whether the scan is typically covered, though they cannot make a final coverage decision without your doctor's medical records. If you have a Medicare Advantage plan, call your plan's customer service number instead, because your plan makes the coverage decision, not Medicare.

Ask the imaging facility for an estimate of your out-of-pocket cost. Facilities are required to provide this estimate before the scan. If the estimate seems high, ask whether the facility is in-network for your plan (if you have Medicare Advantage) or whether they accept Medicare assignment (if you have Original Medicare). Out-of-network or non-participating facilities may charge you more.

What to Do If Medicare Denies Your MRI Claim

If Medicare denies your MRI claim, you will receive a notice called a Remittance information or Explanation of Benefits. This notice explains why the claim was denied. Common reasons include: the scan was not medically necessary, prior authorization was not obtained, or the facility was out-of-network.

You have the right to appeal a denial. Your first step is to ask your doctor's office to appeal on your behalf, providing medical records that explain why the MRI was medically necessary. Your doctor can also request a peer-to-peer review with a Medicare medical reviewer. If your doctor does not want to appeal, you can appeal yourself by sending a written request to the address on your denial notice within 120 days.

If you believe you were billed incorrectly or charged more than your copay or coinsurance, contact the imaging facility's billing department first. If they do not resolve it, you can file a complaint with your state's insurance commissioner or with Medicare's beneficiary advocate line at 1-800-MEDICARE.

Medicare Advantage Plans and MRI Coverage

Medicare Advantage plans must cover MRI at least as broadly as Original Medicare does, but they can set their own copays, deductibles, and prior authorization rules. Some Medicare Advantage plans cover MRI with no copay; others charge $25 to $100 per scan. Some plans require prior authorization for all MRI; others only for certain types.

Your Medicare Advantage plan's coverage rules are in your plan documents, which you receive when you enroll. You can also call your plan's customer service number (on the back of your insurance card) to ask about coverage for your specific MRI before you schedule it. If your plan denies coverage, you can appeal using the same process as Original Medicare.

If you are considering switching from Original Medicare to a Medicare Advantage plan, or vice versa, and you have regular MRI scans, compare the copays and prior authorization requirements. For someone who needs frequent imaging, the difference in out-of-pocket costs can be significant.

Frequently Asked Questions

Do I need a referral from my doctor to get an MRI covered by Medicare?

No, you do not need a formal referral, but your doctor must order the MRI and document that it is medically necessary. The order itself serves as the medical justification. If you try to schedule an MRI without a doctor's order, the facility will not perform it, and Medicare will not cover it.

Will Medicare cover an MRI if I had a CT scan first?

Yes, if your doctor believes the MRI will provide additional diagnostic information that the CT scan did not. Medicare does not require you to have one type of imaging before another. However, if Medicare determines that a CT scan was sufficient and an MRI is not medically necessary, the MRI claim may be denied. Your doctor can explain in the prior authorization request why both scans are needed.

What if my MRI costs more than the Medicare-approved amount?

If you use a facility that participates in Medicare (accepts Medicare assignment), you pay only your copay or coinsurance based on the Medicare-approved amount. The facility cannot bill you for the difference. If you use a non-participating facility, they can charge you more, and you may owe the difference. Always ask whether a facility accepts Medicare assignment before scheduling.

Can I get an MRI covered if I have both Medicare and Medicaid?

Yes. Medicare is your primary payer, and Medicaid may cover some or all of your copay or coinsurance, depending on your state's Medicaid rules. Contact your state Medicaid office to learn what imaging costs Medicaid covers for people with both programs.

Does Medicare cover MRI for back pain?

Medicare covers MRI for back pain if your doctor believes it is medically necessary to diagnose a specific condition, such as a herniated disc, spinal stenosis, or nerve compression. However, Medicare does not cover MRI for general back pain without a documented diagnosis or specific clinical findings. Your doctor must document why imaging is needed before Medicare will cover it.