Common Adjustable Rate Mortgages
ARM Type Months Fixed
10/1 ARM Fixed for 120 months, adjusts annually for the remaining term of the loan.
7/1 ARM Fixed for 84 months, adjusts annually for the remaining term of the loan.
5/1 ARM Fixed for 60 months, adjusts annually for the remaining term of the loan.
3/1 ARM Fixed for 36 months, adjusts annually for the remaining term of the loan.
1 year ARM Fixed for 12 months, adjusts annually for the remaining term of the loan.


Definitions

Fully Amortizing ARM

This is the most common type of ARM. The monthly payment is calculated to payoff the entire mortgage balance at the end of the term. The term is typically 30 years. After any fixed interest rate period has passed, the interest rate and payment adjusts annually. A Fully Amortizing ARM will also have a maximum rate that it will not exceed. This calculator uses a maximum interest rate of 12%. Below is a list of the most common types of Fully Amortizing ARMs.

Interest Only ARM

An Interest Only ARM only requires monthly interest payments during the initial fixed rate period. At the end of the fixed rate period, the loan begins to adjust annually and the borrower makes fully amortizing payments until the end of the term.

Expected rate change


The annual adjustment you expect in your ARM. The range for this calculator is minus 3% to plus 3%. Use a negative value if you believe interest rates will decrease, a positive value if you believe they will increase.

Interest rate

Annual interest rate for each mortgage type. Typically an ARM will have a lower interest rate than a fixed rate mortgage. The rate of an Interest Only ARM will vary by lender.

Months rate fixed


This is the number of months the rate is fixed for an ARM. During this period the interest rate and the monthly payment will remain fixed. The rate will then adjust annually by the expected rate change.

Interest rate cap

This is the maximum interest rate for this mortgage. The mortgage's interest rate will never exceed the interest rate cap.

Monthly payment

Monthly principal and interest payment (PI) for the Fixed Rate Mortgage and the Fully Amortizing ARM. This is an interest only payment for an Interest Only ARM.