Hi Rick, you have the same 7-month initial enrollment period for A and B as you do for Part D. So you can enroll in Part D as late as 3 months after your 65th birthday month. As long as you apply for Part D before that window ends, you won't face any late penalties. Your Medicare supplement open enrollment window lasts for 6 months after your Part B effective date, so if you apply during those 6 months, you won't have to answer any health questions. If you apply more than 6 months past your Part B effective date, you will answer medical questions and go through underwriting.