In an ARM, what is the rate called that is indicated by adding the current index value to the margin?

In an adjustable-rate mortgage (ARM), the rate achieved by adding the current index value to the margin is referred to as the Fully Indexed Rate. This is a crucial concept in understanding how ARMs function. The index reflects the current prevailing interest rates in the market and can fluctuate over time, while the margin is a fixed percentage that lenders add to the index to determine the interest rate on the mortgage loan.

When these two components are combined, they create the Fully Indexed Rate, which ultimately dictates the borrower's interest rate for their loan once adjustments are made. The understanding of this term is essential for both lenders and borrowers, as it impacts the monthly payment and overall cost of borrowing.

Other terms listed do not directly relate to the calculation of the interest rate in ARMs. For instance, "Fully Amortized ARM" refers to a loan structure where payments are calculated to fully repay the loan over a specified term, but it does not explain how the interest rate is determined. "Funding" pertains to the process of providing the loan amount after approval, and "Fannie Mae" is a government-sponsored enterprise that helps provide liquidity in the mortgage market but is not specific to individual ARM rates.