Question
Is interest on a home equity line of credit deductible as a second mortgage?
Answer

It depends. Interest paid on home equity loans and lines of credit is only deductible when you use the proceeds to buy, build or substantially improve your home that secures the loan.

For example, interest on a home equity loan used to build an addition to an existing home is typically deductible, while interest on the same loan used to pay personal living expenses, such as credit card debts, is not. The loan must be secured by the taxpayer’s main home or second home (known as a qualified residence), not exceed the cost of the home and meet other requirements.