Medicare and COBRA--Coverage for Providers Not Participating in Medicare

Hi everyone, I hope that I am posting this question in the correct forum.  Thanks in advance for any input you can give me.

I am 66. My job at a large company ended June 30, 2025.  I enrolled in Medicare so that everything except Part A would be effective July 1 (Part A is retroactive to August 1, 2024).  Specifically, I enrolled in Part B, Plan G, and Plan D and the coverage became effective July 1. 

The information that my employer provided me was confusing as to whether I'd be offered COBRA so it was not in my sights until I just got the COBRA paperwork.  The benefits administrator (a company they engaged to do the billing) confirmed when I inquired that I could be enrolled in both Medicare and COBRA since both started (or would start, for COBRA) on the same day. 

The cost of COBRA coverage, through Aetna, would be $800/month. I would not consider paying that amount since I am already taking a beating through IRMAA, but I have two mental health providers who do not take Medicare. Because of the shortage of good mental health providers, I do not want to switch to someone who does take Medicare just so it costs less.  Therefore, if COBRA would pay the benefits I have become accustomed to, I would at least break even if I did elect COBRA and have Aetna pay as the secondary insurer.

Before I commit to COBRA, I have a few questions that I have not been able to find clear answers for, even when calling Aetna and Medicare.

1. The Aetna representative was obviously not familiar with the complexities of Medicare since she just kept repeating "submit an EOB from the primary insurer" as if that insurer were not Medicare.  Does anyone know how I would get an EOB if the provider does not take Medicare (and therefore would not file a claim)? 
2. Another Aetna rep I spoke to said "if the provider opted out of Medicare, we will cover it."  However, the provider did not strictly opt out, they just don't take Medicare.
3. Do I have to submit the Medicare claim form before submitting to Aetna?  (Section 3 of the form asks about other insurance, so perhaps not?)
4. In terms of the claim form, does anyone know what the difference is between (a) "refused to file a claim," (b) "is unable to file a claim," or (c) "is not enrolled with Medicare."   If I don't go with COBRA and have to file this form, would I choose (c)?
5. If my Plan D coverage has a very high cost for a medication, can I file for reimbursement with Aetna to get my amount down to what I would pay with them?
6. Does anyone have any other cautions about embarking on this somewhat risky plan, since I could end up paying for COBRA and not getting those non-accepting Medicare providers' costs covered?

Thank you so much, and please let me know if any additional information is needed.
Lena

Welcome to the wonderful world of COBRA/Medicare interaction.  As a general rule, the key for anyone age 65+ losing active coverage is to enroll in Medicare asap for a whole host of reasons.  Sounds like you've checked that box, kudos.

Most of the time it is not economically rational to enroll in both Medicare and COBRA--typically it makes much more sense to instead use those funds to pay for Medigap coverage.  But I take your point here that you want to continue to have access to specific providers here that are not available through Medicare.  That could make sense.

You definitely are going to be offered COBRA because you have a loss of coverage caused by termination of employment.  That is a COBRA qualifying event regardless of your age and/or Medicare eligibility.  Just keep in mind that you can lose your COBRA rights if you enroll in Medicare after your COBRA election.  That doesn't appear to be the case here for you, so that's just a heads up.

As to your specific questions--they are very plan/carrier specific so probably nobody here will be able to address them directly.  On the more generic front, once you lose active coverage and have COBRA paired with Medicare, the coordination of benefits rules generally flip.  That means Medicare will pay primary, COBRA will pay secondary.  If the claim is submitted to Aetna in the standard manner by the provider, there should not be any action item for you here.  They will coordinate with Medicare to determine responsibility--which in theory would be solely through Aetna's cost-sharing structure if the provider does not accept Medicare.

There are some cases where you may have to submit a provider bill to the carrier to process a claim that is not handled through the standard channels, but I doubt that would come up often.  I also doubt you would have to submit something from Medicare showing that the provider attempted to bill them and they denied it.  This stuff will probably all be back-end administrative processes that you are not directly involved in.

There's much more info here that may be helpful:

• 2025 Newfront Medicare for Employers Guide

• https://www.newfront.com/blog/the-medicare-form-cms-l564-for-employers

• https://www.newfront.com/blog/how-cobra-and-medicare-interact-for-retirees

Brian Gilmore, I was so grateful to see you response. I read many of your other posts and had fervently hoped you would respond to mine.  I really appreciate it.

Thanks for explaining the machinations of how Medicare interacts with COBRA in terms of the behind-the-scenes billing, etc.   

I am happy to report that I got a written response from Aetna that was clear and helpful.  They said that I would need to submit a letter from the non-participating provider affirming their non-participation and listing some other information.  That is a big relief.  

Thanks again for your input,
Lena