6 2025 SUVs With The Worst Gas Mileage

While it might seem like every car, truck, and SUV continues to climb the ladder of efficiency these days, there are still plenty of low-mpg hold outs. Among SUVs, as it is with most vehicles, poor fuel economy is often tied to potential performance. Big horsepower numbers provided by hefty powerplants tend to be paired with abysmal numbers at the pump, and that's the story with many of the SUVs on our list.

Using the EPA's fuel economy ratings, we've compiled a list of the six SUVs with the worst gas mileage going into 2025. These are the ratings currently available from the EPA for the 2025 model year, so while some upcoming models may beat them out at some point in the year, these top the list as it stands. Under the hood, many of these SUVs pack a big punch, with V6s, V8s, and V12s, on the list. We'll discuss their fuel economy ratings as well as the cost to run these vehicles compared to average fuel economy ratings. A quick note before we get started: keeping in mind that gas prices change over time, the estimates for fuel prices over the life of a vehicle will fluctuate along with prices at the pump. But one factor will almost certainly remain the same: filling up these SUVs isn't for the faint of heart.

Technically, it's a six-way tie for the sixth spot, so we randomly chose the Mercedes-Benz GLS600 to receive the honors. Besides the GLS600, there are five other vehicles that, according to the EPA, check in at 15 mpg combined for the 2025 model year: The BMW X6 M Competition and X5 M competition, Mercedes-Benz AMG G63 and GLS63, and standard Ineos Grenadier. Their city and highway mpg ratings vary slightly, but they're all very expensive to fill up.

According to the EPA, the annual fuel cost for each of these opulent SUVs is a whopping $3,950. The EPA does their math assuming 15,000 miles of driving each year, with 45% of that driving done on the highway and 55% done on city streets. Over five years, you're likely to spend $11,500 more on fuel than the average vehicle owner (the 2024 average fuel economy was 28 mpg). Like most vehicles with big, powerful engines, all these vehicles require premium fuel (91 or 93 octane) — which means no skimping at the gas station if you're trying to cut down the cost. The 2025 GLS600 gets its power from a twin-turbo V8 paired with a 48-volt mild hybrid, producing a total of 550 horsepower. Unfortunately, the mild hybrid system isn't enough to save the GLS from being among the least efficient SUVs made today.

You might not know the Ineos Grenadier name, but you'd definitely notice one if it were parked at your local grocery store. Styled with retro Land Rover Defender vibes, the Grenadier is a boxy, off-road oriented SUV, that makes no compromises in its mission for performance and that's clear from the moment you walk up to it. It has rugged styling, a big snorkel for keeping water out of the engine bay, and on the inside it's filled with switches that look like they belong in an airplane instead of an SUV. Under the hood is an engine sourced from BMW — a turbocharged 3.0-liter V6 that puts out 282 hp and 332 lb-ft of torque.

Many of the other SUVs on this list of big fuel-gulping V8s that produce big horsepower numbers, but that's not the case here. So why such poor fuel economy from the Grenadier's V6? It's likely a combination of factors like its boxy shape which isn't very aerodynamic and the fact that it weighs over 6,000 pounds. The Trailmaster trim also comes on all-terrain tires, which reduce efficiency. The standard Grenadier is rated at 15 mpg combined, as noted in the previous entry, but the Ineos Grenadier Trailmaster is rated slightly worse at 14 mpg across the board — combined, city, and highway. By the EPA's estimates, it will cost $7.07 in gasoline to drive 25 miles in the Grenadier and owners will spend $13,000 extra on fuel over 5 years compared to the average new vehicle.

The ultra-exclusive Rolls-Royce Cullinan holds the distinction of having the largest-displacement engine on our list, which is saying something among these fuel-hungry behemoths. It's powered by a twin-turbo 6.8-liter V12 that puts out 563 hp and 627 lb-ft of torque on standard models (600 horses and 664 lb-ft with the upgraded Black Badge models). 

Curb weight is a hefty 6,069 lbs on base models, and the fuel economy reflects the Cullinan's big power and big numbers on the scale. According to the EPA, the Cullinan will return 14 mpg combined whether you go with the standard model or the more-powerful Black Badge version. This SUV has the same combined mpg as our previous entry, but while the Ineos Grenadier Trailmaster rates 14 mpg for both city and highway, the Cullinan has a dismal 12 mpg city. Thus, we give the Rolls-Royce the number four spot.

Annual fuel cost if you drive 15,000 miles a year is estimated at $4,250, but that shouldn't be a big concern for owners who are spending nearly $400,000 just to get in the driver's seat. Driving those distances over five years will cost Cullinan owners a total of $13,000 more in fuel than average new vehicle buyers.

Powered by a supercharged 6.2-liter V8 that makes 710 hp and 645 lb-ft of torque, the Durango is old school. In fact, it's so old school that almost every other vehicle that once used this powertrain has been killed off by Dodge/Ram. The Hellcat engine was used in the Jeep Trackhawk, various versions of the Challenger and Charger, and the Ram TRX — all of which have been discontinued.

The Durango Hellcat carries on, though, with the Hellcat's signature supercharger whine and all. The Hellcat engine under the hood of a three-row SUV like the Durango is certainly a spicy and expensive way to get the kids to school, with an EPA fuel economy estimate of 13 mpg combined (12 city/17 highway). The EPA also estimates that it'll cost $7.62 to travel 25 miles in the Durango Hellcat, with an annual fuel cost of $4,550, so be sure to include that in your carpool budget.

Like the Durango Hellcat, the Cadillac Escalade-V has an American muscle car vibe under the hood of a three-row SUV. But instead of drag racing and burnouts on its mind, the Escalade-V focuses on luxury family transportation with a big punch packed under the hood. The Escalade-V's supercharged 6.2-liter V8 puts out a whopping 682 hp and 653 lb-ft of torque. The supercharger itself is 2.3 liters of displacement — larger than the displacement of most small four-cylinder compact-car engines. 

Four-wheel drive is standard on the Escalade-V and there are two body lengths available — the standard length and the longer ESV. Curb weights for those two versions of the Escalade-V tip the scales at 6,361 lbs and 6,519 lbs, respectively. All that power and all that weight take a heavy toll on fuel economy, though, with the EPA estimating that the Escalade-V will return just 13 mpg combined (11 city/17 highway). 

This vehicle also ties with the previous entry. Therefore, we once again give the worst spot to the SUV with the lowest city or highway mpg, so congratulations to Cadillac. Compared to the average vehicle (at 28 miles per gallon) the EPA estimates that the Escalade-V will cost you an extra $14,500 in fuel over five years.

The 2025 Purosangue (Italian for "thoroughbred") is the first four-door, four-seat SUV – though it may not look like one at all, with its sports car shape and difficult-to-see rear doors – from Ferrari. And as you'd probably expect from the Prancing Horse brand, it's pretty powerful. The Purosangue is powered by a 6.5-liter V12 (the only naturally aspirated engine on this list) that makes 715 hp and 528 lb-ft of torque. All that power is pricey, though — the starting price for a Purosangue is over $400,000. And when you fill it up, you'll feel the pinch too, or you would if you filled it up yourself instead of having one of your three personal assistants do it.

The Purosangue doesn't just have the worst fuel economy rating of any SUV, it has one of the worst fuel economy ratings of any vehicle you can currently buy. Supercars like the Lamborghini Revuelto and the Bugatti Mistral check in at 12 mpg combined and 9 mpg combined, respectively, and the supercharged Ford F-150 Raptor R is rated at 12 mpg combined, but there isn't much else that can touch a big V12 for poor fuel economy. The Purosangue's official fuel economy rating from the EPA is 12 mpg combined (11 city/15 highway) and they estimate that five years of fuel will cost $16,500 extra compared to the average new car. The fuel cost to travel 25 miles? $8.25. Seems like the sticker price is just the start of your spendy new Italian adventure.