Mazda3 hatchback (2014-2018) - MPG, running costs & CO2

All engines in the Mazda3 offer decent fuel economy and tax-busting CO2 emissions

Carbuyer Rating

3.9 out of 5

MPG, running costs & CO2 Rating

4.0 out of 5

If rock-bottom running costs are a priority – and for many family car buyers, they are – then you could do a lot worse than buy a Mazda3. Thanks to the brand’s innovative SKYACTIV technology, all models are cheap to run, but it’s the powerful diesels that offer the best mix of performance and economy.

Mazda3 MPG & CO2

Just about all versions of the Mazda3 are pretty cheap to run. The entry-level 2.0-litre petrol should return around 55mpg. The more powerful 163bhp 2.0-litre petrol engine will cost more to run, though, with fuel economy of around 48.7mpg. Go for an automatic gearbox – only available on the 118bhp petrol – and your economy will suffer: expect 50.4mpg.

After the first year's CO2-based road tax (generally included in the on-the-road price), all Mazda3s cost £140 a year to tax.

The diesels really stand out when it comes to running costs, though. Most economical of all is the 1.5-litre, which can achieve 74.3mpg and emits 99g/km of CO2 for a 24% company-car tax liability.

If you’re after more power, but similarly low running costs, then the 2.2-litre diesel is well worth a look. It'll return 68.9mpg and emits just 107g/km of CO2 to sit in the 26% BiK company-car tax bracket.

Adding an automatic gearbox does have a pretty significant effect on emissions and fuel economy, however. Switching from the manual to the auto ups CO2 emissions to 127g/km and puts it in the 30% BiK bracket. Fuel economy also drops to around 59mpg.

The diesels’ higher purchase prices compared to the equivalent petrols will be harder to justify for lower-mileage drivers. However, if you’re aiming to keep your car for a while, or cover more than 15,000 miles per year, they’re well worth it.

Insurance group

Insurance is group 16 for the basic 2.0-litre petrol, running to group 21 for the top-of-the-range 2.2-litre diesel Sport Nav model. The entry-level diesel, the 104bhp Sport Nav model is in group 14.


All Mazda3 models come with a three-year, 60,000-mile warranty as standard. They also include a paint and surface corrosion warranty for three years regardless of mileage, as well as a 12-year anti-perforation warranty on body panels. Of course, the warranty is fully transferable to subsequent owners if you’re looking at buying a used Mazda3.

On the subject of buying second-hand, Mazdas have impressive used values that should better those of rivals from Ford, Vauxhall, Peugeot and Hyundai.


Mazda offers fixed-price servicing, making it easy to cover the cost of your car’s regular maintenance. Packages cost around £500 for three years or 37,500 miles of worry-free servicing.

There are also monthly service plans, so rather than paying for your car’s servicing in one go, Mazda will let you spread the cost with affordable monthly payments.

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