Some mistaken assumptions here.
- You will be notified of your Medicare sign-up via letter. They do NOT allow a lot of time to respond so don't put off opening it.
- There is a section that will ask if you have other primary insurance coverage for Parts A, B or D. Answer YES (I assume your current plan has a drug plan reimbursement; if not, answer No to Part D). The reason is that your employer insurance, if it's like 99% of other carriers, wants to now become the secondary carrier with Medicare becoming primary carrier. This change should be seamless and is handled by "back office" operations; nothing should change in how you as the insured, does things.
- You will receive your Medicare card in the mail. Depending on your current insurer, they may or may not need to see your card the first time you come in. My HMO did not and has never needed to ask for it, but your PPO or other HMO may need it, so carry it with you the first few times and ask Reception if they need to make a copy of your card for their files.
- Make a note of your card # - Medicare no longer uses your SocSec # - and you can put your card away in a safe place afterwards.
- Once your employer's insurance ends, you will need to decide if you want to purchase a Medicare supplement or Advantage plan.