What is the purpose of the house? Do you both live in it as your principal residence or just one? Is it an investment or rental? The answer to your question varies depending on the answers to those questions.
The general rule is you must actually pay it and be legally obligated to do so, to deduct it. It is usually best if one you can claim it all, allowing the other to use the standard deduction. But, that depends on the details, including the amounts involved.
