Where do you claim late fees for mortgage payments on your tax return?

Add the late fees to the mortgage interest and enter the total as mortgage interest.

On the screen where you enter the amount of interest there is a box to check that says "The interest amount I entered here is different from what's on my 1098." When you check that box the next screen will ask you to enter an explanation. Enter a brief explanation, such as "Added late payment fees of $xxx."

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