<prompt> Human: I went to file my taxes this year at a local Tax Consultant. In my W4 I had by mistakenly put some dependents which should have been 0. For that reason and over all income I owed government money. I or my wife did not have any 401k or IRA at that time so we owed. But here is the question that I have, my consultant told me that there is a penalty if you owe money to government. Is this true?He also told me that if I owe money next year i.e F.Y. 2015 I will have to pay penalty. He asked me to give him call around October so I can give him mine and my wifes YTD salary so he can go ahead and calculate approximate amount that I will be owing to government and send in that amount check before end of 2015, hence I will not have to pay any penalty. My thinking is, if I owe money to government then I pay government that money when I file for taxes, why does government slap penalty on me. My W4 is 0 this year. Please help me understand the situation.Thanks all in advance.  <response>: He or she may have been referring to the Penalty for Underpayment of Estimated Tax Its a pay-as-you-earn system. In some cases, if you owe 1,000 or more on return due date you can be penalized for not correctly withholding or making estimated tax payments even if you pay in full on the due date. 