what is a 5 1 hybrid adjustable rate mortgage 5 1 arm 
a 5 1 hybrid adjustable rate mortgage 5 1 arm begins with an initial five year fixed interest rate period followed by a rate that adjusts on an annual basis the 5 in the term refers to the number of years with a fixed rate and the 1 refers to how often the rate adjusts after that once per year as such monthly payments can go up sometimes dramatically after five years 1