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• September CPI rose 3.7% year over year, above the 3.6% rate expected before the report.
• Gasoline jumped 9.1% in September and accounted for more than half of the monthly increase in headline CPI.
• Core inflation rose to 2.6%, showing that September's increase was not entirely an energy story.
• May's 4.2% CPI rate remains the 2026 high through September.
• October's next CPI release will lack many normal year-over-year comparisons because BLS does not have corresponding October 2025 data.
September inflation came in slightly hotter than expected, driven largely by another sharp move in energy prices.
The Consumer Price Index rose 0.6% in September on a seasonally adjusted basis and 3.7% from a year earlier, the Bureau of Labor Statistics reported on October 14. Inflation accelerated from 3.4% in August and came in above the 3.6% annual rate expected before the release.
Core CPI, which excludes food and energy, rose 0.3% during the month and 2.6% over the year. That was also hotter than the 2.4% annual core rate expected before the release.
The September report does not establish a new high for 2026. Annual inflation reached 4.2% in May, when core inflation was 2.9%. What September does show is that the path lower remains uneven: energy drove much of the headline acceleration, but core inflation also moved higher.
“we cannot affect any individual price, whether it be oil prices, whether it be foodstuffs at the grocery store.”
Federal Reserve Chair Kevin Warsh, September 2026 FOMC press conference, as quoted by the Federal Reserve Bank of New York.
Gasoline accounted for more than half of the monthly CPI increase. Gasoline prices rose 9.1% in one month, seasonally adjusted, while the broader energy index increased 5.2%. BLS says gasoline alone accounted for more than half of the 0.6% monthly increase in overall CPI.
Gasoline prices were 34.2% higher than in September 2025, fuel oil was up 74.2%, electricity was up 4.4%, and piped natural gas was up 5.0%. Food prices were unchanged during September, while shelter rose 0.4% for the month and 3.2% over the year.
Core CPI increased 2.6% over the year, compared with 2.4% in August. September therefore delivered two signals at once: a large energy shock pushed headline inflation higher, while the broader core measure also moved in the wrong direction. Even then, core CPI remains below May's 2.9% annual rate.
The September CPI-U index reached 336.940, up from 324.800 a year earlier and 335.123 in May. The CPI index measures the price level represented by the consumer basket; the inflation rate measures how quickly that level is changing. Prices can therefore continue climbing even while inflation slows.
CPI is a weighted national measure, not any one household's inflation rate. The Federal Reserve generally uses the Personal Consumption Expenditures price index, or PCE, as its preferred inflation gauge.
Gasoline Prices — September 2026
+9.1%
Seasonally adjusted increase from August to September. BLS says gasoline accounted for more than half of the 0.6% monthly increase in overall CPI.
The next CPI report will come with an unusual limitation. BLS could not collect most October 2025 CPI survey data during the federal lapse in appropriations and did not publish an all-items or core CPI index for that month. It will not publish many normal 12-month percentage changes for October 2026 where corresponding October 2025 data are unavailable.
September was hotter than expected, but the source of the increase matters. Gasoline accounted for more than half of the monthly headline move, while core inflation increased from 2.4% to 2.6%. May's 4.2% annual CPI rate remains the high for 2026 through September.
The more useful takeaway is that inflation has moved down from its spring high without settling into a smooth decline. For households, even that national trend tells only part of the story: the effect of inflation depends on which expenses consume the largest share of a household's own budget.
This article is provided for educational and informational purposes only and does not constitute financial, investment, tax or legal advice.
