Medicare Advantage, Medicare drug plans, fast appeals, and certain hospital-status appeals use different notices and deadlines. Follow the instructions on the notice that applies to your coverage and situation.
1. Confirm that an appeal is the correct route
Use this process when Original Medicare made a coverage or payment decision about a Part A or Part B item or service shown on a Medicare Summary Notice (MSN), and you disagree with that decision. If the issue is a minor claim error or missing information, first ask the provider or supplier whether it can correct and resubmit the claim. A redetermination is not the process for disputing a provider bill that Medicare has not decided.
2. Find the filing date and destination on your MSN
The last page of the MSN gives the appeal deadline and the Medicare Administrative Contractor (MAC) address for that claim. CMS states that a level 1 redetermination generally must be filed within 120 days after receipt of the initial determination and presumes receipt 5 calendar days after the notice date unless there is evidence otherwise. Use the date printed on your MSN rather than relying on a calculation.
If the deadline has passed, you may still request an appeal and explain the good cause that prevented timely filing. The MAC decides whether the explanation is sufficient.
3. Choose a written request method
You may follow the appeal instructions on a copy of the MSN or use the official Medicare Redetermination Request Form, CMS-20027. CMS currently links to the one-page form marked Form CMS-20027 (01/20). Check the official form page before filing in case CMS replaces it.
4. Include the required information
- Your name, address, and Medicare number.
- The specific item or service and date of service you are appealing.
- A clear explanation of why you disagree with the coverage or payment decision.
- Supporting information, such as a provider statement or medical record, when it helps explain why Medicare should cover the item or service.
- Appointment-of-representative documentation if another person is acting for you.
On an MSN copy, circle the item or service being appealed and attach a separate explanation if the space is not enough. Do not send your only copy of an important record.
5. Send the request to the correct MAC
Send the appeal to the Medicare claims office shown in the appeal section on the last page of the MSN. Do not send it to CMS headquarters. CMS notes that many MACs also allow electronic appeal submission, but availability and instructions depend on the contractor. Use the beneficiary-specific notice or the contractor's official website.
6. Keep proof and respond to requests
Keep a complete copy of the request, attachments, envelope or electronic confirmation, and the date sent. The MAC may ask for more information. Send any additional evidence before the redetermination is issued and keep proof of the response.
7. Review the redetermination decision
CMS states that the MAC generally sends its decision within 60 days after receiving the request. This is an administrative timeframe, not a guarantee for an individual case. If the decision remains unfavorable, the notice explains how to request a level 2 reconsideration. Medicare currently states that this next request generally must be made within 180 days after receipt of the redetermination decision.
Official sources
- Medicare.gov — appeals in Original Medicare
- CMS — first-level redetermination requirements
- CMS — Form CMS-20027 and current download
- Medicare.gov — appeal forms