You should have been deducting it against Property A all along. To be deductible, the loan must be secured by your home.
Home Mortgage Interest
This part
explains what you can deduct as home mortgage interest. It includes discussions
on points and how to report deductible interest on your tax return.
Generally, home
mortgage interest is any interest you pay on a loan secured by your home (main
home or a second home). The loan may be a mortgage to buy your home, a second
mortgage, a line of credit, or a home equity loan.
You can deduct
home mortgage interest if all the following conditions are met.
- You file Form 1040
and itemize deductions on Schedule A (Form 1040).
- The
mortgage is a secured debt on a qualified home in which you have an
ownership interest. Secured
Debt and Qualified
Home are
explained later.
Second
home rented out.
-
If you have a second home and rent it out part of the
year, you also must use it as a home during the year for it to be a qualified
home. You must use this home more than 14 days or more than 10% of the number
of days during the year that the home is rented at a fair rental, whichever is
longer. If you don't use the home long enough, it is considered rental property
and not a second home. For information on residential rental property, see Pub.
527.
https://www.irs.gov/publications/p936#en_US_2017_publink1000229900>
