My son lives in house (not my main one) I pay mortgage, insurance, etc. 1) Must I claim rent on that house tho he doesn't pay any? 2) Can I claim it as a 2nd home?

[Hal_Al · Accepted solution]

You have a 2nd home, not a rental unit, since he is not paying rent.

So:

1) You do not have to claim it as a rental unit. In, fact, you are not allowed to claim it as a rental unit. It's not optional. Even if he was paying rent, it would have to be fair market rent to qualify.

2) You can claim it as a 2nd home, because that's what it is. You own it and you family living in it.  You may deduct the mortgage interest and real estate tax, on Schedule A