Mercedes CLA — MPG & Fuel Costs 2025
Mercedes' stylish four-door coupe, sharing platforms with the A-Class but with a sleeker, low-drag aerodynamic profile.
TL;DR
40 MPG
Real-world petrol
53 MPG
Real-world diesel
43L
Tank capacity
£58.82
Full tank (petrol)
15.5p
Per mile (petrol)
Real-World Fuel Economy: The Mercedes CLA achieves an estimated 40 MPG (petrol) and 53 MPG (diesel) in real-world UK driving conditions, accounting for a 12% WLTP real-world penalty.
Forecourt Fuel Cost: Refueling the 43-litre tank completely costs approximately £58.82 (petrol) or £61.10 (diesel) at average UK fuel price rates.
Fuel economy at a glance
40
Real-world MPG
Petrol
47.9
Official WLTP
Petrol
53
Real-world MPG
Diesel
62.8
Official WLTP
Diesel
Annual fuel costs by mileage
| Annual mileage | Petrol | Diesel |
|---|---|---|
| 5,000 miles/yr | £777 | £609 |
| 7,400 miles/yr(UK average) | £1151 | £902 |
| 10,000 miles/yr | £1555 | £1219 |
| 15,000 miles/yr | £2332 | £1828 |
| 20,000 miles/yr | £3109 | £2438 |
| Full tank (43L) | £58.82 | £61.10 |
| Cost per mile | 15.5p | 12.2p |
Based on UK average fuel prices: petrol 136.8p/L · diesel 142.1p/L. Prices updated regularly.
How does the CLA compare?
Tips to get better MPG from your CLA
The CLA is highly aerodynamic; maintaining a steady highway cruise yields excellent MPG.
Use Eco mode to soften throttle response and save fuel in city traffic.
Ensure tyre pressures are adjusted according to load weight to maintain low rolling resistance.
Is the cheaper petrol station worth it?
In a Mercedes CLA achieving ~40 MPG real-world, if you fill 34 litres and the alternative station is 10p/litre cheaper:
£3.40
Gross saving on fuel
£0.47
Cost of 3-mile detour
£2.93
Net saving ✓
You could drive up to 22 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 CLA?
The Mercedes CLA achieves approximately 40 MPG in real-world petrol driving — around 12% lower than the official WLTP figure of 47.9 MPG due to real driving conditions. Diesel variants achieve around 53 MPG real-world.
How much does it cost to fill a Mercedes CLA?
The Mercedes CLA has a fuel tank of 43 litres. At the UK average of 136.8p/litre for petrol, a full tank costs approximately £58.82. Diesel costs approximately £61.10 for a full tank.
What is the annual fuel cost for a Mercedes CLA?
At the UK average annual mileage of 7,400 miles and current petrol price of 136.8p/litre, a Mercedes CLA costs approximately £1151 per year in fuel. At 10,000 miles/year the cost rises to £1555. Actual costs vary with your driving style and mileage.
Is it worth driving to a cheaper petrol station in a Mercedes CLA?
In a Mercedes CLA doing ~40 MPG real-world, driving 3 miles round-trip to save 10p/litre on a 34-litre fill nets approximately £2.93 after the extra fuel cost. You could drive up to 22 miles before the saving is eaten up. Use the WorthThePump calculator for your exact situation.
How much does the Mercedes CLA cost per mile in fuel?
The Mercedes CLA costs approximately 15.5p per mile in petrol at current UK prices. Over a typical commute of 30 miles per day, that is approximately £4.65 per day in fuel.
What is the WLTP MPG figure for the Mercedes CLA?
The official WLTP fuel economy figure for the Mercedes CLA is 47.9 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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