For my self-employed business, I wasn't sure if I could claim the mortgage interest, property tax, and homeowner's insurance as home office deductions if only my spouse's name is on the mortgage loan and the 1098 form. We just bought the house last tax year and are both on the title and deed. Also, if I can claim, can I claim the whole amounts, or only half?
For various reasons, we are Married Filing Separate and using the standard deduction, so neither of us are going to be able to claim the main mortgage interest, etc deductions anyway. So ideally, I would at least like to be able to deduct the proportion of expenses applicable to my home office, which does pass the exclusive use test.