CMS Pub. 100-04, ch. 34, § 10.8

If the reopening action results in a revised determination or decision that results in

payment to a provider, physician, or supplier, a revised electronic or paper remittance

advice notice must be issued by the Medicare contractor and will satisfy the notice

requirements. If applicable, a revised Medicare Summary Notice will suffice for notice

to the beneficiary in the above instances. If the reopening action results in an adverse

revised determination or decision the contractor shall mail, or if approved by CMS,

transmit via a secure Internet portal/application a letter that states the rationale and basis

for the reopening and revision and any right to appeal. The timeframe to request the

appeal would be based on the date of the contractor’s revised determination. If the

contractor cannot change the original determination or chooses to not accept the request,

the contractor should inform the requestor that the contractor cannot process their

reopening request. If the request is over the telephone, the contractor can verbally inform

the caller that they cannot process their request. If it is a written reopening request

submitted via hard copy or a secure Internet portal/application, the contractor shall send a

brief letter via mail or, if approved by CMS, a secure Internet portal/application,

informing the requestor that they cannot process the request. The contractor should state

that their decision to not reopen a claim determination is not an initial determination and

is therefore not appealable.