Your Rate is Tied to an Index
Adjustable-rate mortgages, known as ARMs, differ from fixed-rate mortgages in that the interest rate moves up or down. ARMs are tied to a number of indexes, which usually are published interest rates. The margin is the amount a lender adds to the index, usually two percentage points or four percentage points, to set the actual interest rate of the ARM.
The most common index for ARM adjustments is the one-year U.S. Treasury bill. The one-year bill has a yield very near that offered by the 30-year Treasury bond, which is used to set rates on 30-year fixed mortgages.
The initial ARM rate is generally lower than the fixed mortgage rate.
Is an ARM For You?
If you plan to be in the house for less than five years, it may be worth paying the lower interest rate on an ARM vs. a fixed-rate mortgage.
It may be worth investing the difference between an ARM payment and a fixed loan payment in mutual funds and other investment securities.
If you are unsure of which loan type to choose, check our online loan comparison chart.
Some Facts About ARMs
There are varieties:
Some ARMs adjust the interest rate every year, while others have an initial fixed rate period of 3, 5, 7 or even 10 years, after which the rate adjusts on an annual basis. (3/1 ARM, 5/1 ARM, etc.)Most ARMS offer built-in caps to protect against enormous increases in payments:
The more short term the index that your ARM is tied to, the more volatile your payments will be. That's good if interest rates fall, but it can cause trouble if interest rates rise.
Lifetime cap: Limits how much the interest rate can rise during the life of the loan.Keep in mind that rate caps work when the rates rise and when they fall.
Periodic rate cap: Limits how much your payments can rise at one time.
Payment cap: Offered in some ARMs, it limits the amount the payment can rise over the life of the loan. So if the underlying index rises, your payment would increase only to the limit of the payment cap.
A Final Tip
To keep your financial options open, make sure to ask the mortgage lender if the ARM is convertible to a fixed-rate mortgage. Also, ask if the ARM is assumable, which means when you sell your home the buyer may qualify to assume your existing mortgage.
Continue learning about loan programs and visit the interest only loan programs.
If you are unsure of which loan type to choose, check our online loan comparison chart.
