I share custody of my son with his mother. We each claim him every other year - I claim him in odd years and she claims him in even years. When I claim him my filing status is head of household but when she claims him, my filing status is single. When I did my 2020 taxes (not claiming my son), I noticed my employer did not take any federal taxes out which resulted in me having to pay. I asked my employer about this and they gave me a new W4 to fill out. I am questioning which filing status to choose - single or head of household? I was going to choose head of household since that will be my filing status for 2021 taxes (claiming my son) but then I wondered if I would have to fill out a new W4 next year and change it to single since I won't be claiming my son for 2022. I just want to make sure I have enough taxes withheld so I am not paying again next year. Please help!
First, you might want to make sure you qualify for Head of Household status when you claim your son as a dependent. Just because you claim someone as a dependent doesn’t necessarily qualify you.
Please see the TurboTax Help articles Do I qualify for Head of Household in 2020? and What is a "qualifying person" for Head of Household? for more information.
As far as filing a new Form W-4 each year, that’s probably a good idea, if you can remember to do it. The change would reflect whether or not you had your son as a dependent for the year.