Have a Tax Question? Ask a Tax Expert
Yes. You can do this. If you don't take out enough, you could end up paying an underpayment penalty so you will want to compute the correct amount before you begin.
The IRS does not care how they get their money. This would be a fine way to handle it.
Let me know if you have more questions.
They could compute it for you, but they are not required to do so. I suggest that you ask them to take out a set dollar amount rather than a percentage. Just assume that you will be paying the amount that is your tax rate for the year and average out the dollars. Ask them to withhold this additional amount. If you are taxed at the rate of 27%, ask them to withhold 27% of the 2500.