I do not have a form 1098 and got the interest paid from the bank by phone. I do not know the outstanding mortgage principle (box 2).

[patwmuncey]

If I am not eligible to claim the mortgage interest, I would like to go ahead and complete the return.

[Texas Roger · Accepted solution]

The same person who gave you the interest amount paid over the phone should also be able to tell you what the mortgage principal is. You can go ahead and work on your return and come back to the mortgage section at a later date.

If you normally take the standard deduction instead of itemized deductions, you don't need to enter mortgage interest or any other itemized deduction.  If there was no Schedule A included in your 2018 tax return, then you took the standard deduction in 2018. 

[Carl]

With the possibility of saving you time, be aware of this:

If the total of all of your SCH A itemized deductions (which includes mortgage interest on a maximum of $750K of the outstanding balance) does not exceed your standard deduction, then claiming the mortgage interest as an itemized deduction will have no effect on your tax liability.

So if filing a joint return and the total of all of your itemized SCH A deductions do not exceed $24,600, you're wasting your time itemizing.