The Bureau of Labor Statistics (BLS) reported that the Consumer Price Index for September 2026 rose 3.7% over the past 12 months, before seasonal adjustment. Core prices, which leave out food and energy, rose 2.6% over the same period. Energy prices rose 20.4% over the year. Here is what each figure measures, what it does not, and where to check it.
Source: BLS CPI news release, September 2026
What is the headline number, 3.7% over 12 months?
The all items index is the figure most often quoted in the news. It measures the average change over time in the prices urban consumers pay for a market basket of goods and services. A 3.7% rate means prices were 3.7% higher than a year earlier, not that they rose 3.7% in September alone.
Source: BLS CPI news release, September 2026
Month to month, the all items index rose 0.6% on a seasonally adjusted basis, after a 0.4% rise in August. The 12-month rate is not seasonally adjusted. The BLS summary says the gasoline index rose 9.1% over the month in September, "accounting for over half of the monthly all items increase." One category can therefore move the headline noticeably in a single month.
Source: BLS CPI news release, September 2026
How does core inflation differ?
The core index, "all items less food and energy," rose 2.6% over 12 months and 0.3% in September on a seasonally adjusted basis. The gap between the headline and core 12-month rates is 1.1 percentage points. Core does not replace the headline. Both figures appear in the same release, and each answers a different question.
Source: BLS CPI news release, September 2026
Within the headline, food rose 2.5% over the year and energy rose 20.4%. Both are part of the headline figure but not of core.
Source: BLS CPI news release, September 2026
What does the CPI-U cover?
The CPI-U is the broadest CPI measure. It is based on the spending patterns of urban consumers, who represent over 90 percent of the population. The index is a sample, so it describes the typical household in that group, not every household.
Source: BLS Handbook of Methods, CPI concepts
How to read the numbers in order
1. Check the period. The release covers September 2026 and reports prices that have already been measured.
2. Check the base. The 12-month rates are not seasonally adjusted, while the monthly rates in the summary are. Comparing a monthly rate with a 12-month rate gives a wrong picture.
3. Compare headline with core. The gap shows how much food and energy moved the total.
4. Check the components. Food, energy and gasoline are the first places to look when the headline moves.
5. Open the BLS release tables and match each number to its row before you repeat it.
6. Check the release date. These figures come from the release published October 14, 2026, so newer data may exist.
What does the release not say?
The release describes prices that have already been measured. It does not forecast the next report, and it does not say whether prices will keep rising at this pace. The BLS says the October 2026 CPI is scheduled for release on Tuesday, November 10, 2026, at 8:30 a.m. ET. The index also does not show your own costs. It averages a market basket across many households, so your spending may have moved differently from the average.
Source: BLS CPI news release, September 2026
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