Diesel Price Forecast 2027: What Fleets Should Expect After a Record 2026

Diesel climbed into record territory this fall, and it picked the worst possible time to do it. Prices have been sitting above $6 a gallon heading into winter, right when most fleets are trying to lock in next year’s budget.

This diesel price forecast for 2027 lays out where prices stand now, why 2026 got so expensive, where federal forecasters expect things to head next year, and what  levers you can actually control while the market sorts itself out.

Diesel spent most of 2026 defying the soft forecast it started the year with. By September, the national retail average had reached about $6.29 a gallon, according to the EIA’s October Short-Term Energy Outlook, one of the highest monthly readings the agency has on record. The EIA expects prices to hold above $6 a gallon through October before they begin to ease.

That is a long way from where the year began. Diesel opened 2026 on a downward track, then reversed hard after supply disruptions tied to conflict in the Middle East pushed crude and refined fuel prices up through the spring and summer. By early fall, the weekly retail average had set a new high, topping the prior record from 2022.

The price resets week to week instead of holding near the annual average most budgets are built around, which makes every long-term fuel assumption shakier than it looks on paper.

Also, where you fuel matters just as much as when. Diesel on the West Coast, and in California in particular, runs well above the national average. Because of:

• Tighter regional supply
• Higher state taxes and fees

While much of the middle of the country sits below the average. All and all, the national figure is a useful benchmark, but your real exposure depends on the lanes your trucks actually run.

Diesel is expensive in 2026 because the global market for it is unusually tight, tighter than the market for gasoline. Several forces are stacking on top of each other.

Global production of distillate fuel, the category that includes both diesel and heating oil, has been running below last year’s levels. That has drained inventories and pushed the EIA to raise its diesel price forecast for both 2026 and 2027. U.S. refiners have been running nearly flat out to keep up, hitting around 98% of capacity late in the summer, which leaves almost no cushion if a refinery goes down or demand jumps.

The gap between the price of crude oil and the finished diesel you pump has grown rather than shrunk. Crude still makes up roughly half of what you pay for a gallon of diesel, so the firmer crude prices of 2026 fed straight through to the pump. Tight global supply has also pulled more U.S. diesel into the export market, which keeps domestic inventories lean.

Distillate demand climbs every fall and winter as trucking stays busy and home heating kicks in, while refinery output for diesel often dips in the same stretch. As Work Truck’s 2026 diesel outlook points out, when refineries tilt their production toward gasoline, less diesel reaches the market, and diesel can climb even in months when gas at the pump is getting cheaper.

Most likely, yes, though not all at once. Federal forecasters expect the pressure to let up. The EIA projects retail diesel will average around $4.50 a gallon in 2027, down from the roughly $5 average it expects for the full year in 2026, as global supply loosens and the current tightness fades.

That is a forecast, not a guarantee. Fuel prices are famously hard to call, and this same outlook has already been revised upward more than once in 2026 as real events overtook it. A hard winter, another supply shock, or a shift in how refineries split their output could all move the number in either direction.

In early October, the U.S. government announced a deal for Russia to supply diesel to the global market, backed by a temporary Treasury license, with shipments starting at a few hundred thousand tons and scaling up from there. More supply can help at the margin. That said, the volumes and timing are still uncertain, and added imports do not fix the core constraint, which is how much diesel refineries can actually produce.

Most of the industry is not counting on it to meaningfully move pump prices in the near term. The sensible approach is to plan around the EIA’s baseline and treat any relief from that deal as upside, not something to bank on.

When diesel moves this much, a budget built on a single annual fuel number is often wrong before it is even approved. Fuel is usually the second-largest line in a fleet’s operating cost, behind driver pay, so even a small per-gallon swing compounds fast across a full year of fills.

A fleet of 25 trucks each burning 15,000 gallons a year runs through roughly 375,000 gallons. A 50-cent move in the price of diesel is about $190,000 on that fuel bill, in either direction. That is not a rounding error you can absorb and ignore.

The trap most fleets fall into is treating fuel as a fixed assumption for the year. As Automotive Fleet has reported, oil-market turbulence has made that kind of static planning unreliable, because the underlying price can reset weekly while the budget sits frozen for twelve months.

Fuel surcharges carry the same risk in reverse. If your surcharge is pegged to an old baseline or only recalculates monthly, it lags the real cost of fuel, and you quietly absorb increases you could have passed through to customers.

Checking how often your surcharge resets is one of the cheaper fixes available heading into 2027. The more transparent your fuel card pricing is, the easier all of this gets, because you can see exactly what you paid, where, and when.

Start from the EIA’s 2027 average of about $4.50 a gallon as your base case, then build a cushion around it instead of betting on a single figure. A simple approach is to budget three scenarios:

• A baseline near $4.50
• A high case closer to this year’s $5-plus if supply stays tight
• A low case if relief arrives faster than expected

Update that number as the EIA revises its outlook each month, and tie your fuel surcharge to a current index so it tracks the market rather than lagging it. Lock the cushion into your customer pricing and surcharge terms now, while you have the EIA’s numbers in front of you, instead of trying to renegotiate mid-quarter after a spike has already landed.

The goal is not to predict the price perfectly, which no one can do, but to make sure a bad month does not blow a hole in the plan.

You cannot control the global diesel market, but you can control how much of the damage reaches your bottom line. A few levers matter more than the rest.

Wholesale-based fueling through a CFN cardlock fuel card is priced off daily wholesale benchmarks rather than the retail sign out front, which usually lands a few cents under the pump price. Keeping drivers in-network, instead of filling up wherever happens to be convenient, protects that pricing on every single gallon rather than just some of them.

Having drivers check current fuel prices before they fill helps them route toward cheaper stations, and firm card controls keep spending on-policy. High prices also make theft and misuse more costly per incident, so this is exactly the wrong time to let it slide. Our guide to stopping fuel loss and theft covers where the gallons quietly disappear. Cost control is not only about the price per gallon, it is also about the gallons that leave without ever moving a load.

A simple written fuel policy, backed by card controls that actually enforce it, removes the small judgment calls that quietly add up, like a driver topping off at a premium truck stop two exits past an in-network site.

Clean reporting shows cost per mile, cost per vehicle, and forecast against actual, which is what turns a volatile price into a managed line item instead of a monthly surprise. If you want a practical starting point, our fuel card management tips cover the fundamentals most fleets overlook.

Diesel is expensive right now and likely to stay high through the winter, the EIA expects genuine relief in 2027 with an average near $4.50 a gallon. The smartest thing you can do in the meantime is manage the parts of the bill that are actually yours to manage.

Buy smart, stay in-network, watch for leakage, and build a budget that can flex with the market instead of breaking against it.

If you want help putting that into practice, from wholesale-based pricing to card controls that match how your drivers actually work, talk to an expert on our team. We will walk through what makes sense for your fleet, with no pressure and no runaround.