I should clarify, the 2018 state return with a refund was filed in 2020. On that 2018 state return there was a line where I could apply my 2018 refund to the following year state estimated tax, 2019, which I did. The question is, which year on my federal return can I apply the forwarded 2018 state refund (which became an estimated 2019 state payment) as a schedule A federal deduction? 2020 when the state tax payment was actually made or 2019 which is the tax year that payment is used for.
AND BTW when doing 2019 federal taxes with TT, TT downloads info from 2018 TT from my 2018 federal/state return then applies the state 2018 refund/forwarded payment as a 2019 federal sched A tax deduction. (I'm assuming that the 2019 TT program assumes that I filed the 2018 state return in 2019 not 2020. However the state sends me a 1099 G for year 2020 which says that I received a state refund in 2020 for tax year 2018.
