Canada measures fuel economy the opposite way from the US. Instead of miles per gallon, where higher is better, we use litres per 100 kilometres, where lower is better. That flip trips up many shoppers, especially when browsing American listings or reviews.
How to read L/100 km
L/100 km tells you how much fuel is used over a fixed distance. Lower is better, because less fuel is burned for the same trip.
You will usually see three figures:
- City: Stop-and-go driving with lower average speeds.
- Highway: Steady higher-speed driving.
- Combined: A weighted blend of city and highway, commonly used for comparison.
Use the combined figure for a quick comparison, but look at city and highway separately if your driving is heavily one or the other. Hybrids often shine in city driving, while a diesel or small gas car may do relatively well on the highway.
Where to find official ratings
Natural Resources Canada publishes the Fuel Consumption Guide, a searchable listing of new models, and the EnerGuide label appears on new light-duty vehicles. These ratings come from standardized testing, so they let you compare models on equal terms.
When you shop, check:
- The model year, engine and drivetrain, since ratings change with each
- Whether the figure is for city, highway or combined
- Whether the engine is gas, diesel, hybrid, plug-in hybrid or electric
For used vehicles, find the original rating for that model year, not a newer version.
Comparing fairly
A small number difference can still matter over years. Here is how to turn ratings into cost.
Annual fuel use (litres) = (L/100 km ÷ 100) × kilometres driven per year
Annual fuel cost = annual litres × price per litre
Plug in your own yearly distance and your local fuel price, which changes often. Run the same calculation for each vehicle you are considering. Because fuel prices move, avoid assuming a past price; use the current pump price or run a few scenarios.
| Step | Example approach |
|---|---|
| Pick two vehicles | Compare combined ratings |
| Estimate your yearly distance | Use last year’s odometer readings |
| Calculate litres | Rating ÷ 100 × distance |
| Multiply by fuel price | Use today’s price, then test a higher one |
| Subtract | The gap is your yearly fuel difference |
Then weigh that gap against the purchase price difference. A hybrid may cost more up front but use less fuel; our hybrid vs gas comparison shows how to run that break-even. Fuel is one piece of the larger picture covered in the true cost of owning a car.
Why real-world numbers differ
Labels are a fair way to rank vehicles, not a guarantee of your results. In Canada especially, these factors push consumption up:
- Cold weather. Engines take longer to warm up, air is denser, and winter-grade fuel and heating loads add up.
- Winter tires and snow. Softer rubber and rolling resistance in snow cost some efficiency.
- Short trips. The engine never reaches its efficient operating temperature.
- Idling and remote starts. Fuel burned while stationary gives you zero distance.
- Speed. Wind resistance rises sharply as speed increases.
- Aggressive driving. Hard acceleration and braking waste energy.
- Roof racks, cargo boxes and extra weight.
- Low tire pressure.
- Towing.
Hybrids and electric vehicles are also affected by cold. Heating the cabin and battery in winter can reduce range or efficiency, which is a common surprise. See the electric vehicle buyer guide for what to expect.
Ways to lower your fuel use
- Keep tires inflated to the door-jamb recommendation.
- Remove roof racks and unneeded cargo when not in use.
- Drive smoothly and anticipate traffic.
- Avoid long idling; most vehicles warm up faster by driving gently.
- Combine errands into one trip so the engine stays warm.
- Follow the maintenance schedule, since worn plugs, dirty air filters and wrong oil can hurt economy. See the basic maintenance schedule.
- Use the grade of fuel your manual requires; higher-octane fuel rarely helps an engine designed for regular.
Size and body type matter
Weight, frontal area and aerodynamics set a floor on fuel use. A compact sedan will generally use less than a similar-spec SUV with a similar engine. If you are deciding between body styles, SUV vs sedan compares what you gain and give up. Adding all-wheel drive can also add weight and friction, which usually costs some efficiency.
Reading ratings on US listings
Many online listings and reviews use mpg. Remember:
- US mpg and imperial mpg are not the same, because the gallons differ.
- Convert before comparing: divide 235.2 by US mpg to get L/100 km.
- US test procedures and vehicle specifications may differ from Canadian versions.
If you are considering a US import, check how to import a car from the US, and compare using Canadian figures where possible.
A worked comparison
Say one vehicle is rated at 8 L/100 km and another at 6 L/100 km, and you drive 15,000 km a year. The first uses about 1,200 litres and the second about 900 litres, a difference of roughly 300 litres a year. Multiply that by the current pump price to get your yearly gap, then repeat the exercise at a higher and a lower price. Because fuel prices swing, the range of outcomes is more useful than a single number.
Diesel, hybrid and electric labels
Diesel vehicles often show lower L/100 km figures, but diesel fuel is priced differently and the vehicles can cost more to buy. Hybrids show a single combined figure that already includes the electric assist. Plug-in hybrids may list separate figures for electric and gas operation, so read the label carefully. Electric vehicles are rated by electricity use, so convert using your local electricity rate rather than a fuel price.
Key takeaways
- L/100 km measures fuel used per 100 km; lower is better.
- Use official Natural Resources Canada ratings to compare vehicles on equal terms.
- Convert ratings into yearly litres and dollars using your own distance and current fuel prices.
- Expect higher consumption in Canadian winters, with short trips and with heavy loads.
- When reading US listings, convert mpg carefully and confirm the Canadian rating.
Frequently asked questions
What does L/100 km mean?
It is the number of litres of fuel a vehicle uses to travel 100 kilometres. A lower number means better fuel economy. A vehicle rated at 7 L/100 km uses less fuel than one rated at 9 L/100 km over the same distance.
Why is my real fuel use higher than the label?
Labels come from standardized tests. Real driving involves cold weather, winter fuel blends, idling, short trips, aggressive acceleration, roof racks, heavy loads and winter tires. Cold-weather driving in particular often raises consumption noticeably, so treat labels as a comparison tool, not a promise.
How do I convert between L/100 km and miles per gallon?
The conversion is not a simple multiplication, and US and imperial gallons differ. Because US listings often show mpg, use an online converter or divide 235.2 by US mpg to get L/100 km. Check that you are using the right gallon type.
How are electric vehicles rated in Canada?
Electric vehicles are typically rated by energy use, often shown as kWh per 100 km or an equivalent figure, plus driving range. Official labels also show gasoline-equivalent numbers so you can compare. Check Natural Resources Canada for current label details and guide data.
Informational only. AutoChoice.ca does not sell vehicles or provide financing, insurance, legal or tax advice. Rates, fees and rules change and vary by province; confirm with the dealer, lender, insurer or government agency before you act. See the disclaimer.