Keep in mind also rules if you are / were married. But things are a bit simpler now, they took away some ways you could game the system. (Example, I was born in Nov 53 so at my FRA I started taking my spousal benefit (based on my wife's benefit) while I still let my personal benefit grow (not taking it until age 70).) Note that "SSI" is a welfare program for the poor administered by the SSA. It's not old age / survivor insurance. (And don't forget, you received the "benefit" of survivor insurance even though you didn't have to use it). SSA also administers disability insurance program.
As far as medicare, at age 65 you have to start paying for Part B unless you are still covered at your workplace. If you don't start paying for Part B, you pay a pretty hefty penalty if you want/need to start it after eligible. I guess there's a similar penalty for Part D drug coverage. Also, there's an income "look back" test for Part B (two years), and if you made "too much" they plus up your premium. Medicare Advantage AKA Part C basically "wraps" Part B. I view it as just alternative to a supplement plan and can also provide the Part D drug plan as well. Another wrinkle on the Part B, is if you haven't started your old age pension, in years where there isn't a COLA increase in SS, by law they can't increase Part B on annuitants, and make up the difference by increasing Part B payment for those who haven't started their pension (unless Congress changes the law).
Also Medicare does not coordinate with VA, so if you are in the VA system you need to keep that in mind (in particular if you might want Part B).
scott s.
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