Quick Answer
Medicare providers are required by law to file claims on your behalf for covered services. You should only need to file your own claim in rare situations - such as when a provider refuses to file, when you receive care from an opt-out provider, or when you need reimbursement for emergency care abroad. Use Form CMS-1490S and submit within 12 months of the date of service.
Coverage Comparison by Plan Type
| Plan Type | Coverage | Notes |
|---|---|---|
| Provider Files Claim (Standard) | Provider submits claim directly to Medicare on your behalf | Required by law for participating and non-participating providers; most common scenario |
| You File Claim (Form CMS-1490S) | You submit Form CMS-1490S with itemized bill and supporting documents | Used when provider refuses, is opt-out, or for foreign emergency care |
| Medicare Advantage Claim | Filed through your MA plan, not Medicare directly | Each MA plan has its own claims process and timely filing deadlines |
| Medicare Appeal | Dispute a denied claim or coverage decision | 5-level appeals process; must file within 120 days of denial notice |
Understanding Your Coverage Options
When do You Need to File Your Own Medicare Claim?
Medicare-participating and non-participating providers are required by law to file claims with Medicare on your behalf. You should rarely need to file your own claim. However, there are specific situations where self-filing becomes necessary.
What It Covers
- Your provider refuses to file a claim (this may be Medicare fraud - report it)
- You received care from a Medicare opt-out provider (e.g., some concierge doctors)
- You received emergency or urgent care outside the U.S. in a country with a Medicare reciprocal agreement
- You paid out-of-pocket for a Medicare-covered service and want reimbursement
- Your provider is not enrolled in Medicare but you believe the service is covered
What It Doesn't Cover
- Medicare Advantage claims must go through your MA plan, not Medicare directly
- Part D drug claims must go through your Part D plan
Provider Refusing to File?
If a Medicare-enrolled provider refuses to file a claim on your behalf, this is likely a violation of Medicare rules. Report it to 1-800-MEDICARE (1-800-633-4227) or the HHS Office of Inspector General.
How to File a Medicare Claim: Step-by-Step
To file your own Medicare claim, you'll use Form CMS-1490S, the Patient's Request for Medical Payment. This form is available on the CMS website and must be submitted with supporting documentation.
What It Covers
- Step 1: Download Form CMS-1490S from CMS.gov or request it by calling 1-800-MEDICARE
- Step 2: Complete all sections of the form (patient info, provider info, description of services)
- Step 3: Attach an itemized bill from your provider showing: date of service, description of service, diagnosis/condition treated, provider name and NPI, amount charged
- Step 4: Attach any other supporting documents (referral, prior authorization if required)
- Step 5: Mail the completed form and documents to your Medicare Administrative Contractor (MAC) - the address is on the back of your Medicare Summary Notice (MSN)
- Step 6: Keep copies of everything you submit
What It Doesn't Cover
- Do not send original documents - send copies only
- Claims submitted without an itemized bill will be rejected
Where to Find Your MAC Address
Your Medicare Administrative Contractor (MAC) address is printed on the back of your Medicare Summary Notice (MSN). You can also find it by calling 1-800-MEDICARE or visiting Medicare.gov.
Medicare Claim Filing Deadlines
Medicare has strict timely filing requirements. Missing the deadline means your claim will be denied and you will be responsible for the full cost of the service.
What It Covers
- Original Medicare (Part A & B): Claims must be filed within 12 months (1 calendar year) of the date of service
- Medicare Advantage: Varies by plan - typically 90 days to 1 year; check your plan's Evidence of Coverage
- Part D: Varies by plan - typically 90 days to 1 year after the date of service
- Exceptions may apply for retroactive Medicare enrollment or late enrollment in Medicare
What It Doesn't Cover
- No exceptions are made for late filing due to not knowing about the deadline
- Provider errors do not automatically extend your filing deadline
12-Month Deadline Is Strict
For Original Medicare, the 12-month timely filing deadline is firm. If you paid out-of-pocket for a covered service, file your claim as soon as possible - don't wait.
What Happens after You File
After you submit your claim, Medicare will process it and send you a Medicare Summary Notice (MSN) explaining what was covered, what Medicare paid, and what you owe. If the claim is denied, you have the right to appeal.
What It Covers
- You'll receive a Medicare Summary Notice (MSN) within 30 days of claim processing
- If approved: Medicare pays its share; you receive reimbursement for any overpayment
- If denied: You have 120 days from the MSN date to file a Redetermination (Level 1 appeal)
- 5-level appeals process: Redetermination → Reconsideration → ALJ Hearing → Medicare Appeals Council → Federal Court
Medicare Claim Filing: Key Facts
| Item | Original Medicare | Medicare Advantage | Part D |
|---|---|---|---|
| Who files claim | Provider (or you via CMS-1490S) | Provider files to MA plan | Pharmacy or you to plan |
| Filing deadline | 12 months from date of service | Varies by plan (90 days–1 year) | Varies by plan |
| Form used | CMS-1490S (patient self-filing) | Plan-specific form | Plan-specific form |
| Where to submit | Your Medicare Administrative Contractor (MAC) | Your MA plan directly | Your Part D plan directly |
| Appeal deadline | 120 days from MSN date | 60 days from denial notice | 60 days from denial notice |
✦ Important Exceptions & Special Situations
Opt-Out Providers
Some providers have formally opted out of Medicare entirely. They cannot file Medicare claims, and Medicare will not pay for services from opt-out providers except in emergencies. You must sign a Private Contract with an opt-out provider and pay their full fee out-of-pocket.
Medicare will not reimburse services from opt-out providers (except emergencies).
Foreign Emergency Care
Original Medicare generally does not cover care outside the U.S. However, limited exceptions exist for emergency care in Canada or Mexico if you live near the border, or on a ship within 6 hours of a U.S. port. Some Medigap plans (C, D, F, G, M, N) cover foreign emergency care up to $50,000 lifetime.
Advance Beneficiary Notice (ABN)
If a provider believes Medicare may not cover a service, they must give you an Advance Beneficiary Notice (ABN) before providing the service. If you sign the ABN and receive the service, you may be responsible for the cost if Medicare denies the claim.
Medicare Secondary Payer
If Medicare is your secondary payer (e.g., you have employer coverage), your primary insurer must process the claim first. Medicare then pays the remaining covered amount. Claims must still be filed with Medicare within 12 months.
✦ Recent Updates
CMS Claims Processing Modernization (2025)
PassedCMS updated its claims processing systems in 2025 to reduce processing times and improve the Medicare Summary Notice (MSN) format for beneficiaries.
Medicare.gov Claims Portal Improvements
PassedThe Medicare.gov online portal was updated in 2025 to allow beneficiaries to track claim status, view MSNs, and initiate appeals online.
Medicare Claim Filing Checklist
If you need to file your own Medicare claim, follow these steps to maximize your chances of approval.
Self-Filing Checklist
- Download Form CMS-1490S from CMS.gov
- Obtain an itemized bill from your provider (date, service description, diagnosis, NPI, amount)
- Attach any required supporting documents (referrals, prior authorizations)
- Find your MAC address on the back of your Medicare Summary Notice
- Make copies of everything before mailing
- Mail via certified mail with return receipt for proof of submission
- Track your claim status at Medicare.gov or by calling 1-800-MEDICARE
- If denied, file a Redetermination appeal within 120 days
✦ Frequently Asked Questions
Jagger Esch
AuthorJagger Esch is the founder and CEO of MedicareFAQ and a licensed Medicare insurance agent.
Ashlee Zareczny
ReviewerAshlee Zareczny is the Compliance & Editorial Manager at MedicareFAQ.