The simple answer is yes, if you own a home, and you itemize your deductions on Schedule A, you can claim a deduction for the interest paid. To be deductible, the interest you pay must be on a loan secured by your main home or a second home (including a second home that is also rented out for part of the year, so long as the personal use requirement is met). The loan can be a first or second mortgage, a home improvement loan, or a home equity loan. To be deductible, the loan must be secured by your home but the proceeds can be used for other than home improvements. You can refinance and use the proceeds to pay off credit card debt, go on vacation or buy a car and the interest will remain deductible. There are other financial reasons for not wanting to do this but it will not disqualify the deduction.
The interest deduction for home acquisition debt (that is, a loan taken out after October 13, 1987 to buy, build, or substantially improve a qualified home) is limited to debt of $1 million ($500,000 if married filing separately). The interest deduction from your home equity loan is also not unlimited. You can generally deduct interest you pay on the first $100,000 of a home equity loan. Debt which you incurred to buy, build or substantially improve your home that is in excess of the $1 million home acquisition debt limit may also qualify as home equity debt.
In addition to the deduction for mortgage interest, points paid on the original purchase of your residence are also generally deductible. Taxpayers who are required to pay mortgage insurance premiums may also be able to deduct this amount subject to certain income limits. For more information about the mortgage interest deduction, see IRS Publication 936.