When I imported data from my stock broker, the taxes due more than doubled. Upon further investigation I've noticed that I have to pay AMT. I have capital gains in 2021 and capital loss carryover from 2020 which will offset those gains.
I've started doing research and found this link
https://fairmark.com/general-taxation/alternative-minimum-tax/amt-capital-loss-trap/
If not for the information provided in that website I would have wasted many hours trying to figure out capital loss carryover and AMT
Coming back to the problem in TT, the "Net AMT short-term capital gain/loss" is completely different from "Net short-term capital gain/loss" for year 2020.
For reference if my 2020 "Net short-term capital gain/loss" is -50,000, "Net AMT short-term capital gain/loss" is showing as 130,000. I assume this incorrect amount triggered AMT. However "Net long-term capital gain/loss" and "Net AMT long-term capital gain/loss" from 2020 is exactly the same.
There is no way to find out how TT calculated a different "Net AMT short-term capital gain/loss" amount as I don't have Schedule D AMT in 2020 and all my losses are from simple stock and option trades.
I believe this is a bug in the software. Tax filers unaware of this end up paying thousands in additional taxes.
It will be really helpful if TT keep the "Net AMT short-term capital gain/loss" field blank if it can't find a schedule D AMT from previous year and let the user enter the amount.
Question: Can I correct the "Net AMT short-term capital gain/loss" to reflect the carryover loss from 2020?
