US consumer prices rise 0.6% in September on gasoline surge, core inflation firms

US consumer prices rose 0.6% in September, driven by a 7.1% surge in gasoline costs, pushing annual inflation to 3.7% and increasing the likelihood of a Federal Reserve interest rate hike this month. The core CPI, excluding food and energy, gained 0.3% monthly and 2.6% annually, up from 2.4% in August. The report adds political pressure on President Donald Trump ahead of the November 3 midterm elections, with polls showing voters blaming his policies for rising living costs. Financial markets had assigned roughly a 22% chance of a rate hike at the Fed's October 27-28 meeting before the report. The data also informs the Social Security cost-of-living adjustment for 2027, projected at 3.5%, raising average retiree benefits by $67.90 to $2,007.