But unlike the Supplement (Medigap), I didn't shop long. i don't take any medications (but I probably should), so I didn't carefully compare formularies or anything like that. Just so I had something that didn't look too bad and covered a couple of things I might need. Something so I don't have to pay a penalty for signing up for Part D months or years later when I need it.
The late signup penalty may seem small, but the math is that it's better to buy some minimal plan even if one doesn't use it, for example, than to skip part D coverage until one needs it -- if one expects to live their life expectancy (or somewhat less than their life expectancy -- it's a long time since I did the math and found the breakeven point and posted about it).
The thing is, that penalty, though seemingly small, is life-long, a certain amount a month until one dies. Which seems strange when one only skipped the first year or two, but that's the way it is. (The per month penalty is proportional to the length of time one went without Part D coverage, but it is a lifelong penalty -- a surcharge to what one pays for Part D)
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