What is Federal Income Tax Withholding?
Every time you hire someone, part of your job becomes a tax collector, whether you signed up for that or not. You have to hold back a chunk of each paycheck for federal income tax and send it off to the IRS on the employee's behalf. They never see that money. It skips their bank account entirely and goes toward whatever they'll owe when they file.
The amount isn't something you pick. It comes from the employee's W-4, the form that spells out their filing status and dependents. Most people fill this out once, on their first day, and then never think about it again. That's the problem. Life changes. Somebody gets married. Has a kid. Picks up a second job on weekends. Meanwhile their W-4 is still the one they filled out in 2022, and their withholding has been quietly wrong for who knows how long. Nobody notices until tax season, when they're either writing a check they didn't plan for or getting a refund that's way bigger than it should've been.
None of that is your problem to fix, technically, but getting the withholding calculation itself right? That's on you. Every paycheck, every employee, no exceptions, whether you've got four people on staff or four hundred spread across a few locations.
Most business owners stopped trying to do this math by hand a long time ago. Payroll software handles it now, mostly because it has to keep up with tax tables that shift and W-4 updates that come in whenever they come in. It's not glamorous, but it's one less thing to get wrong while you're busy running the actual business.