“there is a once in a lifetime window that lasts for 6 months after you get your part “B” Medicare (or your 65th birthday for most folks) in which you do not have to have underwriting.” - If I keep working & having employer-sponsored health insurance past age 65 does that push my window out to the date my employer coverage ends? Thank you in advance.
Usually, yes. Some employers require you to have Medicare as your primary (mine doesn't), if so, activating Medicare Part A as your primary might trigger the Part B obligations/rules.
I am going to give you a verbatim list from a United Healthcare booklet, “A Simple Guide to Medicare”, and I would recommend that you pick one of these up or go to Medicare.gov for more information.
Basically, you have a seven-month enrollment period for Medicare (IEP). It begins the month you turn 65, the 3 months before, and the 3 months after. It begins and ends a month earlier if your birthday is on the first of the month.
You may be able to delay enrollment if:
1) The employer has 20 or more employees
2) The employer provided health insurance is considered “credible”
3)The employer doesn’t require the covered spouses to enroll in Medicare at age 65 in order to remain on the employer’s plan.
You must also get a certificate of “credible drug coverage” from the plan administrator. You must have this documentation to avoid a Part “D” penalty if you plan to delay enrollment.
I hope this helps. There is a lot of information available from Medicare.gov that will help you avoid some of the pitfalls of enrolling at the wrong time.