to avoid penalties for not paying in enough taxes on a timely basis when it comes to filing your 2021 return these are the rules.
must have paid in through timely estimates or withholding the lesser of:
90% of 2021 tax
or
110% of 2020 tax (100% if 2020 adjusted gross income was less than $150K)
meeting either test means that you could owe $ millions come 4/15/2022 (for 2021) and not be penalized for not paying enough in.
