US mortgage rates rise by the biggest margin in 11 months, inflation concerns sparked by war with Iran.

The mortgage interest rate in the United States has seen the largest increase in nearly a year, and inflation concerns triggered by the war in Iran have added uncertainty to the upcoming spring sales season. Data released by Freddie Mac on Thursday showed that the average interest rate for 30-year fixed-rate mortgages rose from 6% last week to 6.11%, marking the largest weekly increase since April 2025. Rates briefly fell below 6% at the end of February, and with housing prices stabilizing, the market had some hopes for a slight improvement in the spring sales season. However, if the war continues, oil prices may rise further, pushing up inflation and continuing to put upward pressure on U.S. Treasury yields that guide mortgage rate trends.