WHen renting out a part of your residence, you still enter "ZERO" personal use days. That's because it's asking how many days you used the "rental portion" for personal use. So if you did not use the rental portion that is exclusive to the renter, then you have zero percent personal use days, and ONE HUNDRED PERCENT business use of that space.
While mortgage interest, property insurance and property taxes is split based on the date the rental portion was place in service, and the percentage of space that is exlusive to the renter, you can split utility costs the same way if you want.
Utilities can also be split based on the total number of people living in the house too, if you want. Sometimes that's more beneficial. For example, if you, your spouse and two kids live in the house, and you rent out one room to a single person, that room may only occupy 10% of the total floor space. But with a total of 5 people living in the house, you can apply 20% of the utility expenses to the rental portion.
There is one exception though, and i have no idea why the IRS singles this one out. If the home only has one telephone line then you can "NOT" allocate one single penny of the phone bill to the SCH E. For all the other utilities, they must be available to the tenant. So if there's not a cable TV drop in the space that is exclusive to the renter, you can't apportion part of the cable bill to the SCH E. Weather the tenant actually uses that cable drop or not doesn't matter. So long as it's functional and available for their excursive use, you can claim it.
