I'm examining form 2210. It says multiply 2020 tax liability by 90%. Then it asks how much fed tax withheld and specifies not to include estimated payments. Why wouldn't you? There is $18K or so of investment income that doesn't have taxes withheld. So, shouldn't I be making estimated payments. Fail to understand why they aren't counted against the 90% full tax which is based on W-2 income and investment income.
