Adjustable-Rate Mortgages Gain Traction Amid Rising Fixed Rates

Adjustable-rate mortgages (ARMs) are re-emerging as a significant consideration for prospective homebuyers as interest rates for traditional 30-year fixed mortgages reach new highs. In the final week of September, the average rate for a 30-year fixed mortgage climbed to 7.30%, a level not seen since November 2023, according to data from the Mortgage Bankers Association. In contrast, the average rate for a 5/1 adjustable-rate mortgage stood at 6.47%. This rate differential can translate into substantial monthly savings for borrowers. For instance, on a $400,000 home purchase with a 20% down payment, the initial principal-and-interest payment on a 5/1 ARM could be approximately $178 lower per month compared to a 30-year fixed mortgage at the prevailing higher rate. Hannah Jones, a senior economist at Realtor.com®, highlighted that this affordability gap can be the deciding factor for buyers who would otherwise be priced out of the market entirely. She noted that for individuals who cannot afford a 7% fixed-rate mortgage but can manage payments on a 6% ARM, fixed-rate borrowing might become inaccessible, making ARMs the sole pathway to homeownership. The appeal of ARMs has led to an increase in their market share. In late September, ARMs constituted 10.3% of all mortgage applications, a notable rise from 7% at the start of the year and the highest proportion recorded since October 2025. However, the lower initial payment associated with ARMs comes with inherent risks. Once the introductory fixed-rate period concludes, the interest rate is subject to adjustment, potentially increasing and eventually surpassing the rate a borrower would have paid on a fixed-rate mortgage. The structure of ARMs involves an initial period where the interest rate is fixed, followed by subsequent periods where the rate can change. Common ARM products, such as the 5/1 ARM, feature a fixed rate for five years, after which the rate adjusts annually. A 5/6 ARM follows a similar five-year fixed period but adjusts every six months thereafter. At each adjustment point, the lender applies a predetermined margin to a prevailing market index to determine the new interest rate. While the rate could decrease at a reset, it also has the potential to rise significantly, impacting the borrower's long-term financial obligations. As more consumers turn to ARMs to navigate the current high-interest-rate environment, the critical question for potential buyers becomes whether the immediate financial relief offered by lower upfront payments justifies the potential for higher costs in the future.