Anonymous wrote:We had this problem when we got married. DH had his deductions based on what sounded right versus running the #s. Once we woke up to that, we used to take out extra $ every paycheck toward withholding. Some people even write check every quarter!
In our experience the IRS forgives you for one year of not getting it right. The second year you don't have a major fluctuation in income and don't deduct enough, you get a penalty. Since interest rates are so low anyway, we now overwithhold and then get our taxes done early to get the money back.
In almost all cases if you meet any of the criteria below, you won't have a penalty for underpayment. Your prior history doesn't matter to the IRS. The easiest rule: always make sure you will withhold/pay as much as your total tax last year.
No penalty for underpayment of tax if:
-less than 1k underpaid
-less than 10% underpaid
-withheld at least the amount of tax from last year's return