How the Treasury Sets I Bond Fixed Rates The U.S. Treasury sets the i bonds fixed rate based on prevailing real interest rates. This rate is set twice a year—in May and November—and does not change for the life of the bond. The i bond fixed rate prediction for May 2025 suggests a slight drop from 1.20% to 1.10%, though this could change if real yields shift. Investors often track i b... https://www.federalpensionadvisors.com/post/2025-irmaa-brackets