HSA Contribution for prior year

[Nat007]

Hello Experts,
Here is my situation-
#1. I didn't contribute my HSA in 2020 though I have a high deductible plan with my employer
#2. I have filled my tax returns during mid-Februrary 2021 for the tax year 2020
#3. I have enrolled for HSA account and contributing throughout the year 2021

Can I contribute 2020 HSA from my checking account now (Apr2021) and claim deduction while filing my tax return for 2021?

Thanks!

[Mike9241]

you have until 5/17/2021 to make a 2020 HSA contribution if you qualify.  the 2020 contribution, if you make it, must be claimed on the 2020 return so you'll need to amend it. form 8889 is required.