<prompt> Human: Please bear with me. Ive looked over old posts and couldnt find anything like my situation. My husband and I file married but separately. He claims both children each year. I went back to teaching last year in August after 4 years at home with my young children. There was an issue with my W4 and it appeared that there was an allowance of 16 or some ridiculous number. So when I completed my taxes last year I ended up owing a few hundred dollars only because my income was something like 16k total for 2016. So in May of 2017 I corrected my withholding allowance to Married withholding at a higher single rate with an allowance of 1 So since my withholdings were wrong for a good 6 months of last year I figured my return might be low or I might owe a little bit. Instead I completed my taxes and am owing 800. Ive checked with my payroll department and they say that they are sure that my allowance is recorded as a 1 and married but single rate. I thought at first maybe they never updated my W4. Id be grateful if anyone could check out my numbers and just make sure it looks correct. And tell me if I should be withholding at a 0 for next year. I am in the midst of bankruptcy from medical debt right now and cannot afford to owe right now. So I will have to do an installment plan, if they will let me. Im still paying on the amount I owed last year. This years info:Filed married but separately due to student loan debtAGI: 40,032Total Taxes Paid: 3,177Total Taxes Owed: 801  <response>: here was an issue with my W4 and it appeared that there was an allowance of 16 or some ridiculous number. You just answered your question. Fixing it half way in 2017 would not retroactively withhold the correct amount. Hence you still owe for 2017 tax. 