@eligible
<<In 2021, prior to the deadline, I made an HSA contribution for 2020>>
that HSA contribution goes on your 2020 tax return. Assuming you turned 65 in September, 2020 and you are single, your maximum 2020 contribution was $4550 * 8 /12 or $3033. if you turned 65 prior to September, then the maximum contribution was even less than that.
<<I have found no way to enter my HSA contribution for 2020.>>
because it goes on the 2020 tax return and not the 2021 tax return.
and you can not turn around and say, well then, that contribution in 2021 before the filing deadline was really a 2021 contribution. Since you are on Medicare, you are inelgible to make HSA contributions in 2021.
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