Choosing between a diesel or petrol car isn’t always straightforward. Both fuel types come with their own advantages depending on how and where you drive.
From fuel economy and running costs to performance and emissions, here’s everything you need to know before deciding which option is right for you.
And to understand how factors like fuel type, running costs and market trends influence what your car is valued at, our guide to car valuation hub breaks down everything that shapes a vehicle’s true market worth.
Which Is Cheaper to Buy?
In most cases, diesel cars are slightly more expensive to buy than petrol versions of the same model.
For example, a diesel hatchback will often cost more upfront because diesel engines are more complex and designed for higher-mileage driving.
However, this can vary depending on the type of car.
With some larger executive or performance cars, diesel models can actually work out cheaper than equivalent petrol versions due to lower demand.
If you’re buying a used vehicle, you may also find this helpful:
Should You Buy a High Mileage Car?
Performance: Petrol vs Diesel
Petrol and diesel engines deliver power differently.
Petrol Cars
Petrol engines are usually:
- Smoother to drive
- Quieter
- More responsive at higher revs
- Better suited to sporty driving
Petrol cars are often preferred for:
- Short journeys
- City driving
- Performance-focused driving styles
Diesel Cars
Diesel engines typically offer:
- More torque
- Better pulling power
- Improved motorway cruising
- Stronger fuel efficiency
Diesel cars tend to suit drivers who regularly cover long distances on motorways or A-roads.
Modern diesel engines are also far quieter and more refined than older models.
Which Is Cheaper to Run?
Diesel cars usually offer better fuel economy than petrol cars.
Although diesel fuel can sometimes cost more per litre, diesel engines generally travel further on a full tank thanks to improved miles per gallon (MPG).
Diesel may suit you better if you:
- Drive long distances regularly
- Spend lots of time on motorways
- Need better towing capability
Petrol may be the better option if you:
- Mainly drive in towns or cities
- Cover lower annual mileage
- Want lower upfront costs
If fuel savings and future running costs are important to you, you may also want to read:
Does Charging Your Car Cost Less Than Buying Petrol?
Which Is Better for the Environment?
Traditionally, diesel cars produced lower CO2 emissions than petrol vehicles.
However, diesel engines also produce higher levels of nitrogen oxides (NOx), which has led to tighter emissions regulations and the introduction of Clean Air Zones in many UK cities.
Newer Euro 6 diesel engines are cleaner than older diesel vehicles, but petrol, hybrid, and electric vehicles are becoming increasingly popular due to changing environmental policies.
Your choice may also depend on:
- Local Clean Air Zone charges
- Future government restrictions
- Annual mileage
- Access to charging infrastructure
Petrol, Diesel, Hybrid or Electric?
There’s no one-size-fits-all answer anymore.
The best fuel type depends on:
- How often you drive
- How far you travel
- Your budget
- Running costs
- Future resale value
For motorway drivers, diesel can still make financial sense. For shorter urban journeys, petrol or hybrid vehicles may be more practical.
Thinking About Changing Your Car?
If you’re considering switching from petrol to diesel — or even moving to hybrid or electric — Jamjar can help you to get a value for your current car quickly and easily.
If comparing diesel and petrol cars has you thinking about switching vehicles, our free online valuation tool gives you a quick estimate of what your current car might be worth before you decide.