Why the Fuel Cost Estimates on Car Window Stickers Are So Inaccurate

Car buyers need to check online to get accurate fuel costs because window sticker projections are two years out of date

Fueling a Chevrolet Corvette C7 Photo: John Powers/Consumer Reports

As gas prices soar, the fuel cost estimates printed on new-car window stickers aren’t keeping pace, putting shoppers at a disadvantage when researching models at a dealership. In fact, the one- and five-year projected fuel costs that are required to be printed on every sticker are generally two years out of date.

The national average price for a gallon of regular gas has hovered around $5 this week, up from about $3 a year ago, or by about 60 percent, according to AAA. Because of the price surge, we’ve found some projected fuel costs over five years to be off by more than $10,000 for some vehicles we’ve purchased for our test program. (See specific examples, below.)

The printed window sticker estimates are so out of whack because fuel costs used in the calculations are provided two years in advance to automakers by the Environmental Protection Agency. This means the figures for the 2023 model year were compiled in November 2021 and sent to automakers in December 2021, according to an EPA spokeswoman. The stickers also use the price for regular gas, even when a model calls for more expensive premium fuel.

To get the most accurate information at the dealership, car buyers need to use their smartphone to access a QR code, which is also printed on each window sticker; it provides direct digital access to more accurate market information. Photographing that code opens fueleconomy.gov—the official government source for fuel-economy information run by the EPA and Department of Energy. The site provides near-current fuel pricing, updated weekly, and an interactive calculator that can be used to predict future costs based on a gas price and vehicle MPG.

MORE ON FUEL ECONOMY

Consumers also can find projected annual fuel costs for tested vehicles by accessing our model pages at CR.org/cars. We update our projections when gas prices increase by 50 cents a gallon or more. We last updated the projections on June 22 and set the price for regular in our calculations at $5 a gallon. In our testing, we also calculate each vehicle’s overall MPG using special equipment.

New-car window stickers, also called Monroney labels, list a vehicle’s MPG rating, an emissions rating, a smog rating, and projected fuel costs for one and five years based on data provided to automakers by the EPA, in conjunction with the Energy Information Administration. The window sticker is meant to provide consumers with a full fuel profile so they better understand future costs and the potential environmental implications of driving the car.

In more normal times, when gas supply and prices are generally stable over long stretches, the difference between the printed estimates and those found via the QR code isn’t that significant. But with gas surging above $5 a gallon, we’ve seen that the real costs can be double what’s indicated on the printed window stickers when assessing test cars purchased by Consumer Reports. 

To help consumers understand how a new car might have an impact on air quality, our Green Choice designation highlights the top 20 percent of new vehicles on the market with the cleanest emissions. CR’s Green Choice cars, SUVs, and minivans are indicated in our ratings by a green leaf icon and include gas-powered, hybrid, and electric vehicles. The new Green Choice rating, introduced in early 2021, was developed in collaboration with the EPA’s SmartWay program, which rates vehicles for levels of greenhouse gas and smog-forming emissions.

EPA window sticker
A sample image showing how fuel costs are depicted on window stickers.

Illustration: EPA Illustration: EPA

Comparing Our Window Stickers With Reality

We found significant differences in the estimated costs presented on the window stickers from our recently tested cars compared with what owners will really face right now. Below we break down three examples from cars bought within the past month and explain how the figures are generated.

For the sticker, the EPA assumes a car is driven 15,000 miles, and the calculation is based on its combined MPG rating, merging city and highway test results. The average miles used in the comparison found in the small print on each label are based on the vehicles for that model year, using a specific gas price. 

For the 2022 models, the window stickers state that the average new car gets 27 mpg and costs $6,500 over five years. The 2022 cars cited below use $2.35 price per gallon, despite the fact that the Subaru WRX uses more expensive premium gas. 

In contrast, the window sticker for our 2023 Acura Integra says the average new car gets 28 mpg and costs $8,000 over five years based on $3.65 per gallon.

For our calculations below, we rounded the current national gas price averages to $5 a gallon for regular and $5.70 for premium. 

2022 Ford Maverick
EPA’s combined fuel economy: 37 mpg on regular
EPA’s estimated annual fuel cost: $950
EPA’s estimated five-year fuel cost: $4,765
Estimated annual cost at $5/gal: $2,030
Estimated five-year cost at $5/gal: $10,135 
Five-year difference in window sticker vs. reality: $5,370

2022 Subaru WRX
EPA’s combined fuel economy: 22 mpg on premium 
EPA’s estimated annual fuel cost: $1,600
EPA’s estimated five-year fuel cost: $3,410
Estimated annual cost at $5.70/gal: $8,010
Estimated five-year cost at $5.70/gal: $19,430 
Five-year difference in window sticker vs. reality: $11,420

2023 Acura Integra
EPA’s combined fuel economy: 32 mpg on premium 
EPA’s estimated annual fuel cost: $1,700
EPA’s estimated five-year fuel cost: $8,500
Estimated annual cost at $5.70/gal: $2,670
Estimated five-year cost at $5.70/gal: $13,360
Five-year difference in window sticker vs. reality: $4,800

When fuel prices are relatively stable, these labels are a great resource. For now, buyers are better off using the QR code and fueleconomy.gov. And like most things right now, be prepared to spend more than expected

Correction: This article has been updated with the correct fuel costs for the 2023 Acura Integra.


Jeff S. Bartlett

A New England native, I have piloted a wide variety of vehicles, from a Segway to an aircraft carrier. All told, I have driven thousands of vehicles—many on race tracks across the globe. Today, that experience and passion are harnessed at the CR Auto Test Center to empower consumers. And if some tires must be sacrificed in the pursuit of truth, so be it. Follow me on Twitter (@JeffSBartlett).