Form 1098 does not include ending mortgage principal. What do I include?

[IreneS]

The mortgage principal balance should be in box 2 of the 1098 from your lender.  If you can't find this amount on your 1098, you may find it on your January 2018 mortgage bill.

Try to find the balance and enter it in TurboTax  It is better to enter a figure for your mortgage principal balance, even though it is not listed on the 1098.  Depending on your balance and what you've used the loan for, we'll need this to help you figure out how much interest you can deduct.