All loans have two parts: The “principal”, which is the amount of money that you’re borrowing, and the “interest”, which is the amount of money charged by the lender. Interest-only loans are most commonly used for mortgages. For example, if you borrow $400,000 at a rate of 6% for 30 years, your monthly interest payment would be $1,919.50 and your monthly principal payment would be $478.70. Mortgage payments are normally principal plus interest; in this case $2,398.20.

An interest-only loan allows you to make monthly payments of only the interest for a specific period of time without the principal (although you can always make extra principal payments). The advantage of an interest-only loan is a lower payment. The disadvantage is your loan amount will not go down with each payment, since the principal amount remains unpaid.

Once the interest-only payments end, you will have higher payments for the interest plus principal. You can also refinance the loan or pay it off in full. However, since home prices fluctuate there is a risk that you might owe more on your loan than your house is worth.

Many people with higher income prefer the lower payments because they can use the money that they would normally pay toward principal for investments or other purposes. People with fluctuating income also like interest-only loans because they can make the interest payment when they’re short of funds, and pay down the principal when they have more money like a bonus or commission payment.

Interest-only mortgages are not for everyone, so you should carefully consider if it’s right for you. Contact a mortgage expert to determine the right mortgage for your specific needs.