I so TOTALLY get your question, and am amazed that not only do people not have an answer, they seem to not think there's a real question there. It's obvious that if one person didn't pay enough, say, estimated taxes and therefore owes money, and the other person way overpaid and gets a refund, that a couple is going to want to disentangle that. I believe I heard from a turbotax person on their customer service line that if you do your taxes online (I'm behind and so have been having to use the downloaded TT software), you can click a button to see whether it's more beneficial to file separately/jointly. I would think that even if you're not wondering which system to use, that this way of checking would show how much each of you would owe if you filed separately, and there's your answer. I also found a website that does a quick and dirty calculation of each person's situation to give an estimate of how much each owes, but I can't find the URL at the moment... Karin
