5/1 Adjustable Rate Mortgage (ARM)

A type of home loan for which the interest rate varies during the life of the loan. The mortgage begins with an initial rate that is fixed for a set amount of time, in this case 5 years. The interest rate then adjusts every 1 year for the remainder of the loan, based on fluctuations in market interest rates. The indices used to determine rate adjustment are based on standard tools, such as the 1 year Treasury note or the LIBOR. Nearly all ARMs have an interest rate adjustment cap, beyond which a rate cannot jump in any single 1 year adjustment period. They will also typically have an interest rate ceiling that the adjustments cannot exceed for the life of the loan. Also called 5/1 ARM or 5/1 Hybrid ARM.