Mortgage interest deduction on my residence w/rented room: If I enter full amount in both rental expense and my deductions, will Turbotax calculate for me based on sqft?

[anderlan]

Moreover, will it also auto calculate based not only on percent of square footage rented, but percent of year rented?  I assume I can enter my full utilities and TurboTax will auto calculate based on percent of year and percent of square feet.

[MichaelMc]

TurboTax will make the rental expense allocations that you want. However, do not enter your mortgage interest or real estate taxes in your itemized deductions; that will cause TurboTax to double-count those amounts. Enter the full amount of your real estate taxes and mortgage interest in the rental section. TurboTax will calculate the rental portion and transfer the excess over to your itemized deductions.

[anderlan]

Thank you for that information.  I asked if Turbo Tax would automatically multiply the expenses times the ratio of the rented square feet (it's a room in my house, part of my residence) to the full square feet.  Will it do that?  If so, where do I enter my square feet of rented space and my total?  I checked early in the sequence that I was renting out part of my house, and I have not seen a place to enter square feet used.  I used TT last year and I recall it asked.  I started using HRBlock this year and it also asked.