Refinanced mortgages

If you refinanced a mortgage you had on October 13, 1987, treat the new mortgage as taken out on or before October 13, 1987. However, if you refinanced for more than the balance of the old mortgage, treat only the excess as a mortgage taken out after October 13, 1987.

For more information, see Itemized deductions and review 2017 IRS Publication 936, Home Mortgage Interest Deduction .