<prompt> Human: Hi all,I claimed 0 allowances on my 2015 W-4 and have 0 withheld in federal income taxes. How is this possible? Does this mean I owe taxes?Im single and expect to earn approximately 30K in 2015 altogether. I have only one job. I claimed 0 allowances and 0 additional amount to be withheld from each paycheck.  <response>: Figure out what went wrong so this problem goes away in the future, but yes, you owe money. Its your responsibility to confirm your withholding is correct, and the IRS doesnt care whose fault it is - you earned money and you have, so far, been failing to pay it.If your gross income minus pretax deductions is 30,000, and you take the standard deduction and one personal exemption you are not a dependent and have no other income or adjustments, then your taxable income is 19,700 so your Federal income tax liability is 2,494. If you are a dependent, then you only take the standard deduction, and you will owe 3,094. And, unfortunately, youre going to pay an underpayment penalty, although it will be 100.Also, just to check - they did take out money for Social Security and Medicare, correct? 