Mercedes SL — MPG & Fuel Costs 2025
Mercedes' iconic luxury roadster with a folding metal roof. Outstanding comfort and high-speed cruising refinement.
The Mercedes-Benz SL (R231 generation) is a luxury sports roadster, featuring an all-aluminum body that saved up to 140kg compared to its predecessor.
Engines are smooth and powerful, including turbocharged V6 and V8 petrol units. It is designed to offer effortless high-speed cruising and luxury refinement.
Real-world fuel economy is respectable for a luxury sports car, with the V6 models returning 28-30 MPG on motorway cruises and averaging around 24 MPG in mixed driving.
TL;DR
24 MPG
Real-world petrol
80L
Tank capacity
£109.44
Full tank (petrol)
25.9p
Per mile (petrol)
Real-World Fuel Economy: The Mercedes SL achieves an estimated 24 MPG in real-world UK driving conditions, accounting for a 12% WLTP real-world penalty.
Forecourt Fuel Cost: Refueling the 80-litre tank completely costs approximately £109.44 at average UK fuel price rates.
Fuel economy at a glance
24
Real-world MPG
Petrol
29.4
Official WLTP
Petrol
Annual fuel costs by mileage
| Annual mileage | Petrol |
|---|---|
| 5,000 miles/yr | £1296 |
| 7,400 miles/yr(UK average) | £1918 |
| 10,000 miles/yr | £2591 |
| 15,000 miles/yr | £3887 |
| 20,000 miles/yr | £5182 |
| Full tank (80L) | £109.44 |
| Cost per mile | 25.9p |
Based on UK average fuel prices: petrol 136.8p/L · diesel 142.1p/L. Prices updated regularly.
How does the SL compare?
Tips to get better MPG from your SL
The SL features a lightweight aluminum body; maintain constant speeds to maximize fuel economy.
Keep the folding metal roof closed on long motorway journeys to reduce drag.
Use Eco settings to smooth throttle responses.
Is the cheaper petrol station worth it?
In a Mercedes SL achieving ~24 MPG real-world, if you fill 64 litres and the alternative station is 10p/litre cheaper:
£6.40
Gross saving on fuel
£0.78
Cost of 3-mile detour
£5.62
Net saving ✓
You could drive up to 25 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 SL?
The Mercedes SL achieves approximately 24 MPG in real-world petrol driving — around 12% lower than the official WLTP figure of 29.4 MPG due to real driving conditions. Diesel variants achieve around N/A MPG real-world.
How much does it cost to fill a Mercedes SL?
The Mercedes SL has a fuel tank of 80 litres. At the UK average of 136.8p/litre for petrol, a full tank costs approximately £109.44. Diesel costs approximately £113.68 for a full tank.
What is the annual fuel cost for a Mercedes SL?
At the UK average annual mileage of 7,400 miles and current petrol price of 136.8p/litre, a Mercedes SL costs approximately £1918 per year in fuel. At 10,000 miles/year the cost rises to £2591. Actual costs vary with your driving style and mileage.
Is it worth driving to a cheaper petrol station in a Mercedes SL?
In a Mercedes SL doing ~24 MPG real-world, driving 3 miles round-trip to save 10p/litre on a 64-litre fill nets approximately £5.62 after the extra fuel cost. You could drive up to 25 miles before the saving is eaten up. Use the WorthThePump calculator for your exact situation.
How much does the Mercedes SL cost per mile in fuel?
The Mercedes SL costs approximately 25.9p per mile in petrol at current UK prices. Over a typical commute of 30 miles per day, that is approximately £7.77 per day in fuel.
What is the WLTP MPG figure for the Mercedes SL?
The official WLTP fuel economy figure for the Mercedes SL is 29.4 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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