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In March 2020 I will begin receiving sick pay from my employer, paid through a third party insurer. The forms for the sick pay ask for a specific dollar amount to be withheld from the twice-monthly checks - there is no way to say "withhold at the old single-zero rate' or "withhold highest rate" etc. - they need an exact dollar amount. I know how much pay I will receive (without anything withheld) - how do I figure out what specific dollar amount they should withhold from each check so that I do not end up owing additional tax in 2021? I want it to be about the same as what used to be the 'single zero' rate. Thanks!