We've owed ~$2500 every year for the past five years, and it has really irritated my wife, who is a CPA. Starting in 2014 I have taken full control of the bookkeeping and payroll services for the company I run; we had an accountant doing this stuff and hosting our QuickBoooks previously. My wife helped me set everything up properly on the new file, and almost immediately realized that my correct federal withholding was nearly $100 more than was being withheld the past five years. Some simple math (semi-monthly paychecks 24 x $100) tells us pretty definitively where that money we always owe comes from. Thank you, idiot accountants