Citroen C6 — MPG & Fuel Costs 2025
Citroen's iconic, hydropneumatic executive cruiser. Unmatched comfort, rare presence, and a smooth V6 diesel engine.
The Citroen C6 is a modern classic, famous for its concave rear screen, frameless doors, and active Hydractive 3+ suspension that offers a magic carpet ride.
Built as a French presidential cruiser, it was powered almost exclusively in the UK by smooth 2.7 or 3.0-litre V6 twin-turbo HDi diesel engines mated to automatic gearboxes.
Real-world fuel economy is typical of a heavy luxury car, with V6 models returning 35 MPG in mixed driving, rising to 40 MPG on long-distance motorway cruises.
TL;DR
35 MPG
Real-world diesel
72L
Tank capacity
£98.50
Full tank (petrol)
Real-World Fuel Economy: The Citroen C6 achieves an estimated 35 MPG in real-world UK driving conditions, accounting for a 12% WLTP real-world penalty.
Forecourt Fuel Cost: Refueling the 72-litre tank completely costs approximately £102.31 at average UK fuel price rates.
Fuel economy at a glance
35
Real-world MPG
Diesel
42.8
Official WLTP
Diesel
Annual fuel costs by mileage
| Annual mileage | Diesel |
|---|---|
| 5,000 miles/yr | £923 |
| 7,400 miles/yr(UK average) | £1366 |
| 10,000 miles/yr | £1846 |
| 15,000 miles/yr | £2769 |
| 20,000 miles/yr | £3691 |
| Full tank (72L) | £102.31 |
| Cost per mile | 18.5p |
Based on UK average fuel prices: petrol 136.8p/L · diesel 142.1p/L. Prices updated regularly.
How does the C6 compare?
Tips to get better MPG from your C6
The active rear spoiler rises at speed; maintain a clean boot lid to optimize airflow.
Use smooth, progressive steering and braking to keep the suspension from working hard and drawing power.
Ensure the hydropneumatic suspension is correctly calibrated to maintain low rolling resistance.
Is the cheaper petrol station worth it?
In a Citroen C6 achieving ~35 MPG real-world, if you fill 58 litres and the alternative station is 10p/litre cheaper:
£5.80
Gross saving on fuel
£0.55
Cost of 3-mile detour
£5.25
Net saving ✓
You could drive up to 31 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 Citroen C6?
The Citroen C6 achieves approximately 35 MPG diesel in real-world conditions, around 12% lower than the official WLTP figure of 42.8 MPG.
How much does it cost to fill a Citroen C6?
The Citroen C6 has a fuel tank of 72 litres. At the UK average of 136.8p/litre for petrol, a full tank costs approximately £98.50. Diesel costs approximately £102.31 for a full tank.
What is the annual fuel cost for a Citroen C6?
At 7,400 miles/year and 142.1p/litre diesel, a Citroen C6 costs approximately £1366 per year in diesel.
Is it worth driving to a cheaper petrol station in a Citroen C6?
In a Citroen C6 doing ~35 MPG real-world, driving 3 miles round-trip to save 10p/litre on a 58-litre fill nets approximately £5.25 after the extra fuel cost. You could drive up to 31 miles before the saving is eaten up. Use the WorthThePump calculator for your exact situation.
How much does the Citroen C6 cost per mile in fuel?
The Citroen C6 costs approximately 18.5p per mile in diesel at current UK prices.
What is the WLTP MPG figure for the Citroen C6?
The official WLTP fuel economy figure for the Citroen C6 is 42.8 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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