I have a full-time job and have taxes taken out, but I've also taken on part-time freelancing. How do I pay tax for this income? Can I just up what my employer takes out?

[mmb1]

Hello! Full-time job, taxes are taken out as normal. Instead of figuring out how to pay estimated taxes on the extra, untaxed freelance work, can I just increase the amount taken out by my full-time employer to cover the difference? I just started freelancing and am not sure how many hours this side work will amount to, so I have no idea how/what to pay for estimated taxes. It won't be enough extra income to bump me to the next tax bracket; might be $9k, might be as little as $2k or $3k. Thanks for any help! I've been staring at these Schedule C and 2040-ES forms and am just totally lost.

[MaryK4]

Because it is a new business and you do not know how much you will be making, you can wait until the quarterly estimate is due and make the payment based on what you made that quarter, 15-20% usually is a good amount but of course it depends on your other income.  You also could increase your employer withholding, but you would have the same issue- you cannot be sure how much you will make,