Worst MPG Cars 2026 — Biggest Gas Guzzlers & Their Fuel Cost

Quick answer

The worst-MPG 2026 vehicle is the Ram 1500 at just 12 mpg combined — about $6,400/yr in fuel and 748 g/mi of CO₂. That's roughly $5,350/yr more to fuel than a 50-mpg hybrid. Big trucks, full-size SUVs and exotics dominate the bottom of the list, and 17 2026 models pay the gas-guzzler tax.

Worst MPG

$6,400

Its fuel/yr

Gas-guzzlers

748

Most CO₂ g/mi

Avg car (for scale)

The 2026 worst MPG vehicles

Ranked worst-first by EPA combined MPG, with the real annual fuel cost and CO₂. Mostly trucks, full-size SUVs, performance cars and exotics:

FIG.01

#	Vehicle	Combined MPG	Annual fuel	CO₂ g/mi	Class
1	Ram 1500	12	$6,400	748	Truck
2	Ford Mustang	12	$6,400	741	Car
3	Ford F150	12	$6,400	741	Truck
4	Ferrari Purosangue	12	$6,400	711	Car
5	Cadillac Escalade	13	$5,950	691	SUV
6	Dodge Durango	13	$5,950	659	SUV
7	Chevrolet Corvette	14	$5,500	631	Sports
8	Ferrari 12Cilindri	14	$5,500	619	Sports
9	Jeep Wrangler	14	$5,500	633	SUV
10	Rolls-Royce Cullinan	14	$5,500	609	SUV
11	Rolls-Royce Ghost	14	$5,500	609	Car
12	Rolls-Royce Phantom	14	$5,500	609	Car
13	Chevrolet Silverado	15	$5,150	593	Truck
14	Mercedes-Benz G-Class	15	$5,150	608	SUV
15	Mercedes-Benz GLS-Class	15	$5,150	585	SUV
16	GMC Sierra	15	$5,150	593	Truck
17	Cadillac CT5	15	$5,150	580	Car
18	Porsche 911	15	$5,150	594	Sports
19	BMW X6	15	$5,150	589	SUV
20	BMW X5	15	$5,150	589	SUV
21	Mercedes-Benz S-Class	15	$5,150	603	Car
22	Ford Bronco	15	$4,150	577	SUV
23	Audi SQ8	16	$4,800	540	SUV
24	Chevrolet Suburban	16	$4,800	544	SUV
25	Chevrolet Colorado	16	$3,900	564	Truck
26	Chevrolet Tahoe	16	$4,800	572	SUV
27	Bentley Bentayga	16	$4,800	553	SUV
28	Audi RS	16	$4,800	545	Car
29	Audi SQ7	16	$4,800	540	SUV
30	Mercedes-Benz AMG GT	16	$4,800	558	Sports

ROWS 30·SOURCE EPA fuel-economy database (ForCar) · 2026

Worst variant per model. The flip side: the best MPG cars.

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Which cars pay the gas-guzzler tax?

The federal Gas Guzzler Tax is a one-time penalty (built into the price) on new cars rated under 22.5 mpg combined — it ranges from $1,000 to $7,700 the thirstier the car. It hits passenger cars only (trucks, SUVs and vans are exempt), which is why the list is exotics and performance sedans. 17 2026 models are flagged:

FIG.02

#	Gas-guzzler	Combined MPG	Fuel cost
1	Ferrari Purosangue	12 mpg	$6,400/yr
2	Ford Mustang	12 mpg	$6,400/yr
3	BMW M	13 mpg	$5,950/yr
4	Rolls-Royce Phantom	14 mpg	$5,500/yr
5	Rolls-Royce Ghost	14 mpg	$5,500/yr
6	Chevrolet Corvette	14 mpg	$5,500/yr
7	Ferrari 12Cilindri	14 mpg	$5,500/yr
8	Porsche 911	15 mpg	$5,150/yr
9	Cadillac CT5	15 mpg	$5,150/yr
10	Mercedes-Benz S-Class	15 mpg	$5,150/yr
11	Aston Martin Valhalla	16 mpg	$4,800/yr
12	Mercedes-Benz SL-Class	16 mpg	$4,800/yr
13	Mercedes-Benz AMG GT	16 mpg	$4,800/yr
14	Audi RS	16 mpg	$4,800/yr
15	Aston Martin Vanquish	16 mpg	$4,800/yr

ROWS 15·SOURCE EPA — gas-guzzler flagged · 2026

"Gas-guzzler" here = EPA's official tax flag. The exact tax scales with how far under 22.5 mpg the car falls.

Thirstiest by body type

The single worst-MPG vehicle in each class — the ones to avoid if fuel bills matter:

FIG.03

Class	Thirstiest	Combined MPG	Annual fuel
Truck	Ram 1500	12 mpg	$6,400/yr
SUV	Cadillac Escalade	13 mpg	$5,950/yr
Sports	Chevrolet Corvette	14 mpg	$5,500/yr
Car	Ford Mustang	12 mpg	$6,400/yr

ROWS 4·SOURCE EPA fuel-economy database (ForCar) · 2026

Dirtiest cars by CO₂

Worst MPG means most emissions. These 2026 models put out the most tailpipe CO₂ per mile — the opposite end from the cleanest EVs:

FIG.04

#	Vehicle	CO₂ g/mi	Combined MPG
1	Ram 1500	748 g/mi	12 mpg
2	Ford Mustang	741 g/mi	12 mpg
3	Ford F150	741 g/mi	12 mpg
4	Ferrari Purosangue	711 g/mi	12 mpg
5	Cadillac Escalade	691 g/mi	13 mpg
6	Dodge Durango	659 g/mi	13 mpg
7	Jeep Wrangler	633 g/mi	14 mpg
8	Ferrari 12Cilindri	633 g/mi	14 mpg
9	Chevrolet Corvette	631 g/mi	14 mpg
10	Rolls-Royce Phantom	609 g/mi	14 mpg

ROWS 10·SOURCE EPA fuel-economy database (ForCar) · 2026

Worst MPG — FAQ

What car has the worst MPG?

Among 2026 vehicles, the Ram 1500 is the thirstiest at 12 mpg, about $6,400/yr in fuel.

What is the gas-guzzler tax?

A federal one-time tax on new passenger cars rated under 22.5 mpg combined, from $1,000 to $7,700 depending on how thirsty they are. Trucks, SUVs and vans are exempt — that's why supercars and performance sedans dominate the taxed list.

Why do trucks and SUVs use so much gas?

Weight, size and aerodynamics. A full-size truck or SUV moves 5,000–6,000+ lb with a big frontal area, so it burns far more fuel than a compact — many land in the 12–18 mpg range.

How much does a gas guzzler cost to run?

The worst here burn about $6,400/yr in fuel at 15,000 miles — roughly triple a hybrid. See exactly with the MPG calculator.

What's the opposite — the best MPG?

See the most fuel-efficient cars, or the good-MPG benchmarks by car type.

Fuel-economy, CO₂ and gas-guzzler figures from the EPA (fueleconomy.gov), hosted by ForCar. Rankings are ForCar's own aggregation. Last updated Jul 2026. — ForCar Editorial Reviewed by Denis Kataev, founder of ForCar.

Worst MPG Cars — The Biggest Gas Guzzlers