When entering your 1098 for Mortgage Interest, Box 2 asks for your Outstanding Mortgage Principal as of 01/01/2018. This information should be provided to you on your 1098. 

As you click through the screens, it will then ask you for your balance on 01/01/2019. This information can be found on your monthly mortgage statements or on your lender website if you have account access. 

TurboTax will need the balance at both the beginning and the end of 2018.

Is the balance on 1/1/2019 required information for filing? or only for turbotax information collection purposes?

Same question as hhong19 - I'm in a co-operative and don't have access to balance information for end of 2018. Is it required to file my taxes?

It is not required to be reported to the IRS, but it is needed in order for TurboTax to make the proper calculations. It is used to determine the deductible portion. If the debt exceeds certain amounts ($750,000, or $1,000,000 if the loan was taken before December 15, 2017), then the deduction will be limited.

This information can be found on either a mortgage statement or by contacting your lender.

There is a more in-depth explanation of the 2018 tax reform changes and how it affects your mortgage interest deduction below:

<a rel="nofollow" target="_blank" href="https://ttlc.intuit.com/replies/3300473">https://ttlc.intuit.com/replies/3300473</a>

So as long as the 1/1/19 balance doesn't exceed $750,000 or $1,000,000, the exact balance of the mortgage doesn't not matter and doesn't need to be provided?

We only have to enter the amount of OUR PORTION of the loan correct?