U.S. on-highway diesel averaged $6.199 a gallon on Oct. 5, up $2.488 from a year earlier, the Energy Information Administration said in its weekly price survey. Regular gasoline averaged $4.354, up $1.230 from a year ago. Both prices fell from the prior week, diesel by 18.3 cents and gasoline by 11.1 cents. The agency’s October Short-Term Energy Outlook, released Oct. 6, expects diesel to stay above $6 a gallon this month and gasoline to stay roughly flat before both ease.
How Much Diesel and Gasoline Have Risen
The year-ago prices implied by the EIA’s weekly figures are $3.711 for diesel and $3.124 for gasoline. That makes diesel up about 67% over the year and gasoline up about 39%. The premium diesel carries over gasoline was about 59 cents a gallon a year ago. On Oct. 5 it was $1.845, more than three times as large. For a fleet buying 100 gallons, the Oct. 5 price is $248.80 more than a year earlier, before any gasoline comparison.
The week-over-week declines are small. Gasoline fell about 2.5% and diesel about 2.9% from the prior week, according to the same EIA table. The EIA’s outlook put the September monthly averages at $4.35 for gasoline and $6.29 for diesel. The Oct. 5 diesel reading is about 9 cents below that September average.
Why Diesel Costs More Than Gasoline Right Now
The EIA said gasoline and diesel rose sharply in September because of higher crude oil prices and widening crack spreads, the gap between what refiners pay for crude and what they get for fuel. Distillate crack spreads, which cover diesel, rose throughout the month. Gasoline crack spreads mostly rose early in September.
The agency pointed to inventories. East Coast distillate stocks were 32% below their five-year seasonal average in September. The EIA also cited “extreme tightness in diesel markets” as a factor lifting crude demand, because refiners must run more crude to produce enough diesel.
Supply from the Middle East remains constrained. The EIA said shut-in crude production in the region averaged 4.8 million barrels a day in September, down from 5.8 million in August and a peak of 10.9 million in May. It expects shut-ins of 4.5 million barrels a day in the fourth quarter.
Saudi Pipeline Attacks and the Brent Forecast
Attacks on Saudi Arabia’s East-West pipeline halted flows temporarily in September. Before the attacks the line carried more than 5.0 million barrels a day of exports through Yanbu on the Red Sea. The EIA said the daily Brent spot price reached $131 a barrel on Sept. 15. Repairs allowed partial resumption by Sept. 22.
Shipments through the Strait of Hormuz rose slightly in September as Saudi Arabia increased ship-to-ship transfers along Oman’s coast. Tanker rates hit record highs because of higher insurance costs and longer routes, the agency said. The EIA raised its fourth-quarter Brent forecast by $14 a barrel from last month, to $105. For the full year it expects Brent to average $96 a barrel in 2026 and $84 in 2027.
When Fuel Prices May Come Down
The EIA forecasts retail gasoline at $3.91 a gallon for 2026 as a whole and $3.56 in 2027. It expects prices to stay roughly flat in October and then decline gradually. Diesel is forecast to average $5.19 for 2026 and $4.49 for 2027, and the agency expects it to remain above $4 a gallon through next year.
The outlook puts Brent’s September average at $114 a barrel, $23 above August. The fourth-quarter forecast of $105 is therefore $9 below September’s average. The same outlook document includes a winter fuels section. It says households that heat with oil face a 21% rise in spending this winter, while natural gas and propane households will spend less than last winter. East Coast distillate stocks are forecast to hit a low of 22.6 million barrels in April, 21% below average, so the tightness that lifted diesel in September is projected to persist into spring.
Wholesale declines will not reach drivers and truckers immediately. The EIA said retail and distribution margins were squeezed by the surge in wholesale prices, so sellers are likely to rebuild margins before cutting pump prices. The agency expects most regional production to return to pre-conflict averages by the end of the second quarter of 2027.
The outlook’s macroeconomic assumptions show how much room households have to absorb the higher costs. It projects real disposable personal income growth of 0.5% in 2026, rising to 3.1% in 2027, and a 3.7% rise in the GDP price deflator this year against 2.1% next year. The EIA outlook does not estimate how much of the 3.7% comes from fuel.
Other household energy costs look different. The outlook puts Henry Hub natural gas at $3.48 per million Btu for 2026, down from a January average of $7.72. It puts wholesale electricity at $52 per megawatt-hour in 2026, 11% above 2025, and residential retail electricity at 18.21 cents per kilowatt-hour, rising to 18.68 cents in 2027. Oil-linked fuels are where the year-over-year increase is steepest. The next weekly price update is scheduled for Oct. 14.
