I need advice. This year I am thinking of filing separate return instead of the usual joint return. Our incomes are high but not too close. I earn about 140K and she earns about 95K. If we file separate returns and itemize, are there complications with deductions? I itemize deductions every year. One of those deductions is a sizable mortgage interest deduction. Do we need to claim half of this deduction for each of us if we file separate return? Or can one of us claim the entire mortgage interest deduction while the other one claims our child as dependent. The mortgage is paid in full by me with no contribution from her and I feel that the deduction should be mine alone in case we file separately. What does the IRS require in this case? Thanks.