In-depth Reviews

Porsche 718 Boxster roadster - MPG, running costs & CO2

The Porsche 718 Boxster’s switch to turbocharged four-cylinder engines has significantly reduced running costs

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MPG, running costs & CO2 Rating

3.5 out of 5

If you’re buying a two-seater, convertible sports car capable of nearly 180mph and a 0-62mph time of around five seconds, then your priorities are likely to lie somewhere other than fuel economy. Still, like all other manufacturers, Porsche is under pressure to reduce its exhaust emissions, and that brings big advantages to buyers, too.

Porsche 718 Boxster MPG & CO2

Thanks in part to its fuel-efficient, four-cylinder engine, the entry-level Boxster claims economy of up to 32.5mpg when fitted with the six-speed manual gearbox. This improves to 33.2mpg if you opt for the PDK twin-clutch automatic transmission. These numbers equate to CO2 emissions of 180 and 186g/km for a car with the automatic or manual gearbox respectively, resulting in the top rate company-car Benefit-in-Kind (BiK) band of 37%. Unsurprisingly, given it has the same engine and power, the figures are virtually identical for the Boxster T.

If you go for the more powerful Boxster S, running costs increase. The most economical version (fitted with the PDK gearbox) will return around 30.7mpg, dropping to 29.1mpg if you go with the standard six-speed manual gearbox. Which gearbox you choose has the same effect on CO2 emissions as it does with the standard Boxster; PDK versions emit 194g/km and manual models register 210g/km.

The extra power of the GTS means it's the thirstiest of the Boxster range, returning 28.5mpg and emitting 210g/km of CO2 with a manual gearbox.

All Boxsters cost £145 a year in road tax but because the car costs over £40,000, every version faces a £320 surcharge in years two to six, bringing the annual total to £465 during that period.


The Porsche 718 Boxster sits in insurance group 44 out of 50, while the Boxster S sits in group 46. Groups for the GTS haven’t been released yet, but are likely to be slightly higher again. Considering the car’s technology, power and badge appeal, plus the added vulnerability of a folding fabric roof, insurance costs are predictably high.


All new Porsches get a three-year manufacturer warranty. There are no mileage restrictions and owners also benefit from European roadside assistance within the first three years. This puts the Boxster on par with its rivals from BMW and Mercedes. There’s also the option of adding an extra year onto that initial three-year warranty for extra peace of mind, and extending the warranty can also help you sell the car if and when you decide to do so.


If you’re considering a Boxster, be aware of the fairly significant maintenance costs. Brakes and tyres will both be expensive to replace and will wear out quickly if you put the car through its paces regularly.

Servicing costs will be steep, too. A minor service is likely to cost around £400, with this increasing to more than £600 for a major service. The only silver lining is the fact that these are only required (alternating with one another) every two years or 20,000 miles.

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