Mercedes C-Class — MPG & Fuel Costs 2025
Mercedes' executive saloon and estate. Available with efficient mild-hybrid petrols and diesels, plus a plug-in hybrid option with a massive electric range.
The Mercedes-Benz C-Class is an executive car that places a strong emphasis on comfort, technology, and interior design. The latest generation features a portrait touchscreen inherited from the flagship S-Class and a highly refined ride.
All engines feature some level of electrification, with mild-hybrid systems assisting the petrol and diesel units. The C 300e plug-in hybrid is a standout model, featuring a large battery that allows for an electric-only range of up to 60 miles.
Real-world fuel economy is highly competitive. The C 220d diesel returns an average of 50 MPG on the motorway, making it a brilliant business tool. The petrol C 200 manages around 37 MPG, offering quiet running and good comfort.
TL;DR
37 MPG
Real-world petrol
50 MPG
Real-world diesel
66L
Tank capacity
£90.29
Full tank (petrol)
16.8p
Per mile (petrol)
Real-World Fuel Economy: The Mercedes C-Class achieves an estimated 37 MPG (petrol) and 50 MPG (diesel) in real-world UK driving conditions, accounting for a 12% WLTP real-world penalty.
Forecourt Fuel Cost: Refueling the 66-litre tank completely costs approximately £90.29 (petrol) or £93.79 (diesel) at average UK fuel price rates.
Fuel economy at a glance
37
Real-world MPG
Petrol
43.5
Official WLTP
Petrol
50
Real-world MPG
Diesel
58.9
Official WLTP
Diesel
Annual fuel costs by mileage
| Annual mileage | Petrol | Diesel |
|---|---|---|
| 5,000 miles/yr | £840 | £646 |
| 7,400 miles/yr(UK average) | £1244 | £956 |
| 10,000 miles/yr | £1681 | £1292 |
| 15,000 miles/yr | £2521 | £1938 |
| 20,000 miles/yr | £3362 | £2584 |
| Full tank (66L) | £90.29 | £93.79 |
| Cost per mile | 16.8p | 12.9p |
Based on UK average fuel prices: petrol 136.8p/L · diesel 142.1p/L. Prices updated regularly.
How does the C-Class compare?
Tips to get better MPG from your C-Class
For the C 300e PHEV, utilize the battery-hold mode on the motorway to save charge for local city driving.
Keep speeds down on high-speed roads to utilize the car's sleek aerodynamics for optimal MPG.
Check tyre pressures before long trips; a heavy load in the estate version can drag down mileage if tyres are low.
Is the cheaper petrol station worth it?
In a Mercedes C-Class achieving ~37 MPG real-world, if you fill 53 litres and the alternative station is 10p/litre cheaper:
£5.30
Gross saving on fuel
£0.50
Cost of 3-mile detour
£4.80
Net saving ✓
You could drive up to 32 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 Mercedes C-Class?
The Mercedes C-Class achieves approximately 37 MPG in real-world petrol driving — around 12% lower than the official WLTP figure of 43.5 MPG due to real driving conditions. Diesel variants achieve around 50 MPG real-world.
How much does it cost to fill a Mercedes C-Class?
The Mercedes C-Class has a fuel tank of 66 litres. At the UK average of 136.8p/litre for petrol, a full tank costs approximately £90.29. Diesel costs approximately £93.79 for a full tank.
What is the annual fuel cost for a Mercedes C-Class?
At the UK average annual mileage of 7,400 miles and current petrol price of 136.8p/litre, a Mercedes C-Class costs approximately £1244 per year in fuel. At 10,000 miles/year the cost rises to £1681. Actual costs vary with your driving style and mileage.
Is it worth driving to a cheaper petrol station in a Mercedes C-Class?
In a Mercedes C-Class doing ~37 MPG real-world, driving 3 miles round-trip to save 10p/litre on a 53-litre fill nets approximately £4.80 after the extra fuel cost. You could drive up to 32 miles before the saving is eaten up. Use the WorthThePump calculator for your exact situation.
How much does the Mercedes C-Class cost per mile in fuel?
The Mercedes C-Class costs approximately 16.8p per mile in petrol at current UK prices. Over a typical commute of 30 miles per day, that is approximately £5.04 per day in fuel.
What is the WLTP MPG figure for the Mercedes C-Class?
The official WLTP fuel economy figure for the Mercedes C-Class is 43.5 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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