In my case, I continued with my employer health coverage beyond age 65 and have 8 months to sign up for Medicare now that my employment and coverage has ended.. I wanted to keep as much of my HSA contributions as possible.
However, when I recently discovered that COBRA coverage would only pay as a secondary insurance whether or not I have signed up for Medicare, since I am Medicare eligible, I didn't want to risk paying high out of pocket charges (equivalent to what Medicare would have covered) for the next 6 months. That's when I gave up on the my plan to delay Medicare signup for 6 months, and did the Return of Excess for my HSA. I was surprised how long it took me to learn this about COBRA coverage when you are Medicare eligible.
