US · guidance
CMS Pub. 100-04, ch. 29, § 310.5
The Redetermination Decision
A. Redetermination Decision Letters
The law requires contractors to conclude and mail and/or otherwise transmit the redetermination decision
within 60 days of receipt of the appellant's request, as indicated in §310.4. For unfavorable
redeterminations, the contractor mails the decision letter to the appellant, and mails copies to each party to
the initial determination (or the party’s authorized representative and/or appointed representative, if
applicable).
Contractors shall mail the written decision unless the contractor has received approval from CMS to use a
secure Internet portal/application as part of the appeals process and the appellant has submitted the request
for appeal electronically. Contractors may transmit appeal decisions (favorable, partially favorable, or
unfavorable) via a secure Internet portal/application if the appeal request was received via that mechanism.
Contractors shall ensure that a hard copy decision letter is sent to other parties to the appeal who do not have
access to the secure Internet portal/application. See §310.10 for additional requirements related to notices
sent via secure portal/ applications.
For partially favorable redeterminations, the contractor mails and/or otherwise transmits the decision letter,
and an adjusted MSN or RA to the appellant. The contractor mails a copy of the decision letter and mails or
otherwise transmits an adjusted MSN or RA to each party to the initial determination (or the party’s
authorized representative, if applicable). The contractor shall ensure that the appropriate MSN or RA
messages are included regarding refunds of payments, including when necessary any coinsurance or
deductible collected.
If a party has an appointed representative, the contractor mails the decision letter to the appointed
representative (see §270). Sending the decision letter to the appointed representative has the same force and
effect as if the letter was sent to the party. The contractor does not send an MSN or RA to an appointed
representative.
For fully favorable redeterminations, the contractor mails or otherwise transmits an MSN or RA reflecting
the adjustment action to each party (or the party’s authorized representative, if applicable) on the next
scheduled release. The MSN provides the beneficiary with information as to his/her financial liability with
regard to the claim(s) that are now payable (e.g. applicable coinsurance). The contractor does not send an
MSN or RA to an appointed representative.
Unless otherwise specified in its statement of work, contractors are not required to send a fully favorable
letter to parties until further notice, except in those situations where the parties will not receive notice of
effectuation via an MSN or RA (e.g., MSP overpayments, non-MSP overpayments which do not result in a
refund or payment, etc.). In these cases, the contractor mails and/or otherwise transmits via secure Internet
portal/application a notice to such parties or authorized/appointed representative if applicable, that references
the claims appealed, and briefly explains the outcome of the redetermination.
B. Determinations That Result in Refunds to a Beneficiary
If, as the result of a denial, a provider or supplier is required to make a refund to a beneficiary for amounts
collected from the beneficiary for the items or services at issue, then the contractor must include the
following language in the redetermination:
“Therefore, you (the beneficiary) are not responsible for the charges billed by (provider's name) except for
any charges for services never covered by Medicare. If you (the beneficiary) have paid (provider's name) for
these services (including payment of co- insurance and deductible), you may be entitled to a refund. To get
this refund, please contact this office and send the following items:
• A copy of this notice,
• The bill you received for the services, and
• The payment receipt, your cancelled check, or any other evidence showing that you have already paid
(provider's name) for the services at issue.
You should file your written request for refund within 6 months of the date of this notice.”
If, as the result of a denial, a provider or supplier is required to make a refund to a beneficiary for amounts
collected from the beneficiary for the items or services at issue, then the contractor must send a copy of the
adjusted RA in the following situations:
1. A nonparticipating physician not accepting assignment who, based on the redetermination, now has a
refund obligation under §1842(l)(1) of the Act;
2. A nonparticipating supplier not accepting assignment who is determined to have a refund obligation
pursuant to §1834(a)(18), due to a denial under either §1834(a)(17)(B) or §1834(j)(4) of the Act; or,
3. A denial based on §1879(h) of the Act of an assigned claim submitted by a supplier, where it is
determined under §1834(a)(18) of the Act that the supplier must refund any payments (including
deductibles and coinsurance) collected from the beneficiary.
NOTE: For additional information regarding refund requirements, please refer to IOM 100-04 Chapter 30,
sections 140 and 150.
C. Paid Claim Appeals
If a contractor receives a valid appeal request on a claim that was processed and paid subsequent to the filing
of that appeal but prior to issuance of the Medicare Redetermination Notice, the contractor shall issue an
unfavorable decision letter using the following template or something similar to the appellant:
(Start)
EXHIBIT 1:
MONTH, DATE, YEAR
APPELLANT NAME MEDICARE NUMBER OF
ADDRESS BENEFICIARY:
CITY, STATE ZIP
CONTACT INFORMATION:
If you have questions, write or call:
Contractor Name
Address
City, State Zip
Telephone number
RE: <Include claim identifier or appeal number>
Dear <Appellant Name>:
This letter is to inform you of the decision on your Medicare appeal. An appeal (also
known as a redetermination) is a new and independent review of a claim. You are
receiving this letter because you requested a redetermination for <SERVICE(S)> on
<DATE(S)>.
The redetermination decision is unfavorable because the service(s) in question has(have)
already been paid by the MAC on <DATE>. We have evaluated the information
submitted and there do not appear to be any errors impacting the payment amount, which
Model Redetermination
Unfavorable Decision
for
Paid Claim Appeal
is the maximum allowed by Medicare for this service. As a result, we are issuing an
unfavorable decision on your request for a redetermination on this claim.
If you disagree that the claim in question was previously processed for payment, and/or
you otherwise disagree with this decision, you may appeal to a Qualified Independent
Contractor. You must file your appeal, in writing, within 180 days of receipt of this
letter, to the following address:
[INSERT QIC INFORMATION]
Sincerely,
NAME, TITLE
CONTRACTOR NAME
(End)
Exhibit 1
History
(Rev. 3549, Issued: 06-24-16, Effective: 07-26-16, Implementation: 07-26-16)
Provenance
- Source
- cms.gov
- Retrieved
- 2026-08-25
- Edition
- iom-2026-08-25
- Content hash
3d7de24a95f7d2da1e04bdee101faf7f70c277b1e3b5f1830ac78b61b9f68219
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