A tax court ruled (Wheeler, TC Summ. OP. 2011-83) that a taxpayer could not deduct mortgage interest on payments she made on her boy friend’s house that she also lived in. The facts presented during the trial also showed that she paid the entire mortgage at one point, was the only wage earner, paid for some home improvements and was later made a co-owner and added to the mortgage.
The Court denied her deduction for the mortgage interest paid before the date that she became an owner saying that she had no ownership interest, had no right to the profits if it were sold and did not bear the risk of a loss.
So the answer is: you can only deduct interest if the home is in your name.
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