How to Submit a Claim to Medicare

What happens when you submit a Medicare claim

When you submit a claim to Medicare, you are sending a record of a medical service or item you received, along with what it cost, so Medicare can decide whether to pay for it. Most of the time, your doctor's office or hospital submits the claim for you automatically — you do not have to do anything. If you do need to submit one yourself, you send the paperwork to the Medicare contractor in your region, not to a central Medicare office.

The contractor reviews your claim against Medicare's rules for that service. They check whether you were covered on the date of service, whether the service itself is covered, and whether the provider is in-network. If everything matches, they pay the provider or reimburse you. If something does not match, they deny the claim and send you a notice explaining why.

The whole process usually takes two to four weeks from the date Medicare receives your claim, though it can take longer if they need more information from you or your provider.

Key Takeaways

Your doctor or hospital submits most Medicare claims automatically, so you do not need to file anything yourself.
If you do submit a claim yourself, you send it to your regional Medicare contractor, which you can find on Medicare.gov or by calling 1-800-MEDICARE.
You will need the provider's name and billing information, your Medicare number, the date of service, and an itemized receipt or invoice showing what was billed.
Medicare sends you a notice called an Explanation of Benefits (EOB) that shows what they paid, what you owe, and the reason for any denial.
If Medicare denies your claim, you have the right to file an appeal, and you have one year from the date on the denial notice to do so.

When you need to submit a claim yourself

In most cases, your provider files the claim for you. But there are situations where you may need to file it yourself. If you paid out of pocket at the time of service — perhaps because the provider did not accept Medicare or you went out of network — you can submit a claim for reimbursement. If a provider says they submitted a claim but you never received an Explanation of Benefits, you may need to file it again to make sure Medicare has a record.

You should also submit a claim yourself if you received a service from a provider who does not normally bill Medicare. This can happen with certain mental health providers, some dentists (if they are treating a covered condition), or providers in other countries if you were traveling.

What documents you need before you submit

Gather these items before you contact Medicare or your contractor:

Your Medicare card or your Medicare number
The provider's full name, address, and billing information (usually on your receipt or invoice)
The date you received the service
An itemized receipt or invoice showing what was billed and how much
Proof of payment if you paid out of pocket (a credit card statement, check, or receipt)

If the service was ordered by a doctor, bring the order or prescription as well. This helps Medicare see that the service was medically necessary.

How to find your regional Medicare contractor

Medicare contracts with different companies in different regions to process claims. You need to send your claim to the contractor that serves your state. You can find your contractor in two ways.

Go to Medicare.gov, click on "Contacts," and enter your state. The site will show you which contractor handles claims in your area and their mailing address. You can also call 1-800-MEDICARE (1-800-633-4227) and ask which contractor serves your region. The representative will give you the address and may also tell you whether that contractor accepts claims by mail, fax, or online portal.

Some contractors have online portals where you can submit claims electronically, which is faster than mailing paper forms. Ask when you call whether your contractor offers this option.

How to fill out and submit the claim form

If you are submitting a claim on paper, use Form CMS-1500 (the standard Medicare claim form) or Form CMS-1450 if the service was provided at a hospital or facility. You can read both forms from Medicare.gov. The forms ask for your name, Medicare number, date of birth, the provider's information, the date of service, what was done, and how much was charged.

Fill in every field that applies to your situation. If a field does not explore, leave it blank rather than writing "N/A." Attach copies (not originals) of your receipt, proof of payment, and any medical orders. Write your Medicare number on the back of each page you attach.

Mail the completed form and documents to the address your contractor provided. Keep a copy for your records. If you are using your contractor's online portal, follow their instructions for uploading documents — most portals let you submit the form and attachments in one step.

What to expect after you submit

After Medicare receives your claim, they send you an Explanation of Benefits (EOB). This document shows what service was billed, what Medicare paid, what you owe, and the reason for any denial. The EOB is not a bill — it is a record of what happened with your claim.

If Medicare paid the provider directly, the EOB shows that amount. If they reimbursed you, the check or electronic transfer usually arrives within two weeks of the EOB. If Medicare denied the claim, the EOB explains why — for example, "not medically necessary," "not covered," or "provider not in network."

Keep your EOB with your medical records. If you have questions about what it says, call the number on the EOB to speak with someone at your contractor.

How to appeal a denied claim

If Medicare denies your claim and you disagree with the decision, you can appeal. You have one year from the date on the denial notice to file an appeal. The appeal process has five levels, and most people resolve their case at level one or two.

To start an appeal, write a letter to your Medicare contractor explaining why you think the claim should be paid. Include your Medicare number, the date of service, and a copy of the denial notice. Explain what service you received and why you believe it was medically necessary or covered. Attach any new information that supports your case — for example, a letter from your doctor saying the service was necessary.

Mail your appeal letter to the address on the denial notice. The contractor will review it and send you a decision, usually within 30 days. If you disagree with that decision, you can request a hearing before an independent reviewer. The process becomes more formal at that stage, but you do not need a lawyer to appeal.

Frequently Asked Questions

Do I have to submit a claim if my doctor's office says they will?

No. If your provider says they will submit the claim, you can wait to see if Medicare processes it. If you do not receive an Explanation of Benefits within four weeks, call your provider to confirm they submitted it. If they did not, you can submit it yourself using the same documents they would have used.

What if I lost my receipt?

Contact the provider's billing office and ask for an itemized statement of what was billed to Medicare. They can print a copy or email it to you. This document serves the same purpose as a receipt for your claim.

Can I submit a claim online instead of by mail?

Some Medicare contractors accept online submissions through their portal. Call your contractor or check their website to see if this option is available in your region. Online submission is usually faster than mailing paper forms.

What if Medicare says the provider is not in-network?

Out-of-network providers can still bill Medicare, but Medicare may pay less or deny the claim depending on the service. If the claim was denied for this reason, you can appeal and explain why you used that provider — for example, if it was an emergency or the in-network provider was not available. Include any documentation that supports your reason.

How long does it take to get paid after I submit a claim?

Medicare usually processes claims within two to four weeks. If they need more information from you or your provider, it may take longer. You can check the status of your claim by calling your Medicare contractor or logging into your Medicare account on Medicare.gov.

This guide is for general information only and is not medical, financial, legal, or other professional advice. For decisions specific to your situation, consult a qualified professional. See our Editorial Policy.