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BLS average price

How much did diesel fuel cost in September 2021?

Diesel fuel averaged $3.37 per gallon in September 2021.

$3.37

per gallon in September 2021

Adjusted with CPI-U, that is about $4.14 in 2026 dollars.

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Source: U.S. Bureau of Labor Statistics Average Price Data, APU000074717. Imported from BLS bulk time-series files (raw published monthly values).

Related historical prices

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Diesel fuel prices in October 2021
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Data: U.S. Bureau of Labor Statistics — CPI-U. Series CUUR0000SA0, base period 1982–84 = 100. Coverage: 1913–2026. April CPI is used for 2026 until the annual average is published.

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