If all you have is a W-2 and minimal deductions, in my experience it's pretty close unless you think +- $1K is "a bunch."
Once you have dividends, stock sales, mortgages, other revenue, etc. your employer really has no way to know what the right amount to deduct is. If you're consistently over or under, you can change the number of allowances on a W-4 form.
>Some people choose to not deduct any
You can take a large number of allowances but I'm not sure you typically can just not take any deductions. If you significantly underpay you may get hit with a penalty and will have to make estimated tax payments the following year.
Once you have dividends, stock sales, mortgages, other revenue, etc. your employer really has no way to know what the right amount to deduct is. If you're consistently over or under, you can change the number of allowances on a W-4 form.
>Some people choose to not deduct any
You can take a large number of allowances but I'm not sure you typically can just not take any deductions. If you significantly underpay you may get hit with a penalty and will have to make estimated tax payments the following year.