An adjustable-rate mortgage (ARM) is a type of mortgage in which the interest rate applied on the outstanding balance varies throughout the life of the loan. With an adjustable-rate mortgage, the initial interest rate is fixed for a period of time, after which it resets periodically, often every year or even monthly.
A variable rate mortgage is another name for an ARM, which takes a number of different forms. Floating rate mortgage is another name for one. A variable-rate mortgage, or ARM, has an interest rate reset based on a benchmark or index, plus an additional spread, called an ARM margin—Read more at Investopedia. Kagan, Julia. “Adjustable-Rate Mortgage (ARM).” 28 August 2019.