Porsche Boxster — MPG & Fuel Costs 2025
Porsche's mid-engined roadster, offering sublime handling and efficient four-cylinder turbo engines.
The Porsche Boxster (718 generation) switched to turbocharged four-cylinder boxer engines, which greatly improved low-end torque and overall fuel efficiency compared to the older flat-six models.
The mid-engined layout provides perfect balance and handling, making it one of the most engaging roadsters on sale in the UK.
In terms of fuel cost, it is highly efficient when cruised, returning around 30 MPG real-world, making it a very usable weekend touring car.
TL;DR
30 MPG
Real-world petrol
54L
Tank capacity
£73.87
Full tank (petrol)
20.7p
Per mile (petrol)
Real-World Fuel Economy: The Porsche Boxster achieves an estimated 30 MPG in real-world UK driving conditions, accounting for a 12% WLTP real-world penalty.
Forecourt Fuel Cost: Refueling the 54-litre tank completely costs approximately £73.87 at average UK fuel price rates.
Fuel economy at a glance
30
Real-world MPG
Petrol
34.9
Official WLTP
Petrol
Annual fuel costs by mileage
| Annual mileage | Petrol |
|---|---|
| 5,000 miles/yr | £1036 |
| 7,400 miles/yr(UK average) | £1534 |
| 10,000 miles/yr | £2073 |
| 15,000 miles/yr | £3109 |
| 20,000 miles/yr | £4146 |
| Full tank (54L) | £73.87 |
| Cost per mile | 20.7p |
Based on UK average fuel prices: petrol 136.8p/L · diesel 142.1p/L. Prices updated regularly.
How does the Boxster compare?
Tips to get better MPG from your Boxster
Keep the roof closed on long motorway journeys to reduce drag and save up to 5% fuel.
Utilize the engine's strong mid-range torque by short-shifting in manual mode.
Run high-quality super unleaded 97+ RON fuel to keep the turbo combustion clean.
Is the cheaper petrol station worth it?
In a Porsche Boxster achieving ~30 MPG real-world, if you fill 43 litres and the alternative station is 10p/litre cheaper:
£4.30
Gross saving on fuel
£0.62
Cost of 3-mile detour
£3.68
Net saving ✓
You could drive up to 21 miles round-trip before the saving disappears entirely.
Calculate for your exact situationPopular variants
Frequently asked questions
What is the real-world MPG of the Porsche Boxster?
The Porsche Boxster achieves approximately 30 MPG in real-world petrol driving — around 12% lower than the official WLTP figure of 34.9 MPG due to real driving conditions. Diesel variants achieve around N/A MPG real-world.
How much does it cost to fill a Porsche Boxster?
The Porsche Boxster has a fuel tank of 54 litres. At the UK average of 136.8p/litre for petrol, a full tank costs approximately £73.87. Diesel costs approximately £76.73 for a full tank.
What is the annual fuel cost for a Porsche Boxster?
At the UK average annual mileage of 7,400 miles and current petrol price of 136.8p/litre, a Porsche Boxster costs approximately £1534 per year in fuel. At 10,000 miles/year the cost rises to £2073. Actual costs vary with your driving style and mileage.
Is it worth driving to a cheaper petrol station in a Porsche Boxster?
In a Porsche Boxster doing ~30 MPG real-world, driving 3 miles round-trip to save 10p/litre on a 43-litre fill nets approximately £3.68 after the extra fuel cost. You could drive up to 21 miles before the saving is eaten up. Use the WorthThePump calculator for your exact situation.
How much does the Porsche Boxster cost per mile in fuel?
The Porsche Boxster costs approximately 20.7p per mile in petrol at current UK prices. Over a typical commute of 30 miles per day, that is approximately £6.21 per day in fuel.
What is the WLTP MPG figure for the Porsche Boxster?
The official WLTP fuel economy figure for the Porsche Boxster is 34.9 MPG. However, real-world MPG is typically 10–15% lower than WLTP due to cold starts, air conditioning, motorway speeds, and varying loads. WorthThePump uses a 12% real-world penalty to give a more accurate estimate.
Related guides
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