You can usually deduct the interest you pay on a mortgage for your main home or a second home.
Here are the answers to common questions about this deduction:
Mortgage interest is any interest you pay on a loan secured by a main home or second home. These loans include:
If the loan is not a secured debt on your home, it is considered a personal loan and the interest you pay isn't deductible.
For the IRS, a home can be a house, condominium, cooperative, mobile home, boat, recreational vehicle, or similar property that has sleeping, cooking, and toilet facilities.
Your home mortgage must be secured by your main home or your second home. You can't deduct interest on a mortgage for a third home, a fourth home, and so on.
You do, if you are the primary borrower, you are legally obligated to pay the debt, and you actually make the payments. If you are married and both you and your spouse sign for the loan, then both of you are primary borrowers. If you pay your son's or daughter's mortgage to help them out, however, you cannot deduct the interest unless you co-signed the loan.
Yes, your deduction is limited if all mortgages on your home total either:
Your deduction may also be limited if your home-equity loans are more than $100,000 ($50,000 if you're married and filing separately).
In the above cases, your deduction may be limited. For details, see IRS Publication 936, Home Mortgage Interest Deduction.
Here are a few special situations you may encounter.
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If all your mortgages fit one or more of the following categories, you may deduct all of the interest paid on your mortgages.
If a mortgage does not meet these criteria, your interest deduction may be limited. To figure out how much interest you can deduct in that situation, see IRS Publication 936, Home Mortgage Interest Deduction.
If you had a grandfathered mortgage and refinanced it, the mortgage balance replaced by the new mortgage remains grandfathered.
Example: Your principal mortgage balance on October 13, 1987 was $51,000. On April 15, 1989, you borrowed $101,000. You used that money to pay the existing loan (which had a balance of $49,000) and all your credit cards, then used the rest of the loan proceeds to buy a new car. Of the total amount borrowed, $49,000 is grandfathered and $52,000 is a home-equity loan.
In the event of an IRS inquiry, you'll need the records that document the interest you paid. These include:
Form 1098 is the statement your lender sends you to let you know how much mortgage interest you paid and, if you purchased your home in the current year, any deductible points you paid. Sometimes, these forms don't look like tax forms; scan the statement you get in January looking for the words "Form 1098."
If you paid more interest than your Form 1098 shows, you must attach a statement to your tax return that explains why you're deducting more than your lender reported on Form 1098.
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Updated for tax year 2007

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