2004 Toyota Prius: MPG and fuel economy

This page collects every fuel-economy figure the EPA publishes for the 2004 Toyota Prius. Below you will find the headline combined, city, and highway MPG, the estimated annual fuel cost at three different driving levels, the tailpipe CO₂ emissions, and a full breakdown of the engine and drivetrain. If you want to know whether this generation got more or less efficient over the years, the year-over-year table further down covers every model year the EPA has rated.

Fuel economy at a glance

These are the EPA's official ratings for the 2004 Toyota Prius. The numbers come from a standardised laboratory test cycle and are the same figures that appear on the window sticker of every new car. Real-world mileage varies with driving style, weather, fuel quality, and how heavily loaded the car is.

Combined MPG is a 55/45 weighted blend of the city and highway test cycles. The EPA uses it as the single number you can compare across the entire dataset, including hybrids and EVs (which use the equivalent MPGe figure).

How the 2004 Toyota Prius compares

The 2004 Toyota Prius returns 46 combined MPG. Cars in the Midsize Cars class for the same model year average 20.8 MPG, which puts this car ahead of the class average by about 121%.

Within the Midsize Cars class for the 2004 model year, the Toyota Prius is the leader. No other car in the same class beat its 46 MPG rating. The bar chart below shows it alongside the class average and the average new car for some additional context.

For broader context, the average new car of the 2004 model year (across all classes) returns 18.4 MPG. Larger vehicles pull the all-cars average down, so do not use that figure on its own to judge a small car or a hybrid. The full list of the most efficient cars of the 2004 model year is on its own page.

Annual fuel cost across driving patterns

The headline annual fuel cost the EPA publishes assumes 15,000 miles of driving per year and a fuel mix of 55% city and 45% highway. The dollar figure is calculated using the EPA's current reference price for regular gasoline, which is $3.99/gallon. EPA updates that reference periodically rather than tracking live pump prices, so treat it as a window-sticker estimate rather than today's pump number.

The table below scales the EPA's number to three common driving patterns. The combined MPG and the reference fuel price stay constant, only the annual mileage changes. To get a current-prices estimate, take your local gas price and multiply by 326.1 gallons (the car's annual consumption at the rated MPG).

Year-over-year MPG for the Toyota Prius

The EPA has rated the Toyota Prius across 26 model years, from 2001 Toyota Prius through 2026 Toyota Prius. The numbers below are the best combined MPG figure the EPA published for each year, which lets you see when the car was at its most efficient and how recent generations stack up.

The 2001 Toyota Prius returned 41 MPG. The most recent 2026 Toyota Prius returns 57 MPG. That is an improvement of 16 MPG over 25 model years, the kind of gain that usually comes from smaller engines, hybrid systems, or aerodynamic redesigns.

Compare against other Midsize Cars for 2004

If you are cross-shopping the 2004 Toyota Prius, the most useful comparison is against the other cars in the Midsize Cars class for the same model year. The list below shows the highest-MPG peers, ranked from most to least efficient. Click any of them to open its full page.

Specifications

The 2004 Toyota Prius runs a 1.5-liter 4-cylinder engine paired with a automatic (variable gear ratios), sending power through front-wheel drive.

Engine, transmission, and drivetrain together drive most of the variation in fuel economy across trims. A larger engine moves the car with less effort but burns more fuel. A turbo lets a small engine punch above its weight, often without much MPG penalty. All-wheel drive adds traction and weight, and usually costs a couple of MPG compared with two-wheel drive of the same engine.

Vehicle class

Midsize Cars

Engine

1.5L 4-cylinder

Transmission

Automatic (variable gear ratios)

Drivetrain

Front-Wheel Drive

Fuel type

Regular

Annual petroleum use

6.5 barrels per year

Start-stop system

Yes

Common questions about the 2004 Toyota Prius

Quick answers to the questions people most often search for when looking up the 2004 Toyota Prius.

• Is the 2004 Toyota Prius fuel efficient?

  Yes. The 2004 Toyota Prius returns 46 combined MPG, which beats the average car in the Midsize Cars class for the same model year by about 121%.
• What MPG does the 2004 Toyota Prius get?

  The EPA rates the 2004 Toyota Prius at 46 combined MPG, 48 MPG in city driving, and 45 MPG on the highway. Real-world numbers depend on your driving style, the weather, and how loaded the car is.
• How much does it cost to fuel a 2004 Toyota Prius per year?

  The EPA estimates an annual fuel cost of $1,300 for the 2004 Toyota Prius. That figure assumes 15,000 miles of driving per year, a 55% city and 45% highway split, and the EPA's published average fuel price for the rated fuel grade.
• What fuel does the 2004 Toyota Prius use?

  The EPA lists the 2004 Toyota Prius as running on regular gasoline. Using a different grade than the manufacturer specifies can affect fuel economy and engine longevity.
• Has the Toyota Prius become more fuel efficient over time?

  Yes. The first EPA-rated Toyota Prius, the 2001 Toyota Prius, returned 41 combined MPG. The most recent 2026 Toyota Prius returns 57 MPG, an improvement of 16 MPG over the run.
• How much CO₂ does the 2004 Toyota Prius emit?

  Tailpipe CO₂ emissions are 193 g/mi. Multiplied across a typical year of driving (15,000 miles) that works out to about 2,898 kilograms of CO₂.
• What is the difference between the city and highway MPG of the 2004 Toyota Prius?

  City driving returns 48 MPG and highway driving returns 45 MPG. A flat (or city-better) split is the signature of a hybrid or electric drivetrain, where regenerative braking recovers energy that would otherwise be lost in stop-start city traffic.
• What engine is in the 2004 Toyota Prius?

  The 2004 Toyota Prius has a 1.5-liter 4-cylinder engine.
• What transmission and drivetrain does the 2004 Toyota Prius have?

  The 2004 Toyota Prius comes with a automatic (variable gear ratios) transmission and front-wheel drive.
• Is the 2004 Toyota Prius the most efficient car in its class?

  Yes. Among cars in the Midsize Cars class for the 2004 model year, the Toyota Prius returns the highest combined MPG at 46 MPG. No other car in the same class beats that figure.

Source: U.S. EPA fuel economy dataset. Annual fuel cost figures assume 15,000 miles of driving per year and a 55% city, 45% highway split. Real-world mileage varies with driving conditions, vehicle maintenance, fuel quality, and driver behaviour.