We both have w2 jobs, she makes about half what I make and apparently it isn't enough because her employer doesn't withhold federal tax but mine does. Our w4s are the same, entered 2 kids and checked the box in section 2. We had to owe this year at filing time, and had an underpayment penalty. To avoid this for next year at tax time, can I just increase my withholdings to compensate for hers? If so, would I just take the amount we had pay and divide that by my remaining paychecks in 2025 and have that withheld as additional? Assuming our income and tax situation is the same.
