Lexus IS — MPG & Fuel Costs 2025
Lexus' sharp-looking executive saloon, offering hybrid efficiency, comfort, and bulletproof reliability.
The third-generation Lexus IS is a premium executive saloon designed to compete with the BMW 3 Series, featuring sharp styling and a high-quality interior.
While older versions featured a 2.2-litre diesel or a thirsty 2.5-litre V6, this generation is dominated by the IS 300h self-charging hybrid model.
Real-world fuel economy for the hybrid model is excellent, returning around 45 MPG in daily driving, making it a very economical and reliable company car choice.
TL;DR
33 MPG
Real-world petrol
44 MPG
Real-world diesel
66L
Tank capacity
£90.29
Full tank (petrol)
18.8p
Per mile (petrol)
Real-World Fuel Economy: The Lexus IS achieves an estimated 33 MPG (petrol) and 44 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
33
Real-world MPG
Petrol
39.2
Official WLTP
Petrol
44
Real-world MPG
Diesel
55.4
Official WLTP
Diesel
Annual fuel costs by mileage
| Annual mileage | Petrol | Diesel |
|---|---|---|
| 5,000 miles/yr | £942 | £734 |
| 7,400 miles/yr(UK average) | £1395 | £1086 |
| 10,000 miles/yr | £1885 | £1468 |
| 15,000 miles/yr | £2827 | £2202 |
| 20,000 miles/yr | £3769 | £2936 |
| Full tank (66L) | £90.29 | £93.79 |
| Cost per mile | 18.8p | 14.7p |
Based on UK average fuel prices: petrol 136.8p/L · diesel 142.1p/L. Prices updated regularly.
How does the IS compare?
Tips to get better MPG from your IS
For IS 300h hybrid models, use Eco mode and accelerate smoothly to stay in electric-only EV mode in town.
Use the regenerative braking system to keep the hybrid battery charged by braking progressively.
Check tyre pressures regularly to prevent rolling resistance from lowering your MPG.
Is the cheaper petrol station worth it?
In a Lexus IS achieving ~33 MPG real-world, if you fill 53 litres and the alternative station is 10p/litre cheaper:
£5.30
Gross saving on fuel
£0.57
Cost of 3-mile detour
£4.73
Net saving ✓
You could drive up to 28 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 Lexus IS?
The Lexus IS achieves approximately 33 MPG in real-world petrol driving — around 12% lower than the official WLTP figure of 39.2 MPG due to real driving conditions. Diesel variants achieve around 44 MPG real-world.
How much does it cost to fill a Lexus IS?
The Lexus IS 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 Lexus IS?
At the UK average annual mileage of 7,400 miles and current petrol price of 136.8p/litre, a Lexus IS costs approximately £1395 per year in fuel. At 10,000 miles/year the cost rises to £1885. Actual costs vary with your driving style and mileage.
Is it worth driving to a cheaper petrol station in a Lexus IS?
In a Lexus IS doing ~33 MPG real-world, driving 3 miles round-trip to save 10p/litre on a 53-litre fill nets approximately £4.73 after the extra fuel cost. You could drive up to 28 miles before the saving is eaten up. Use the WorthThePump calculator for your exact situation.
How much does the Lexus IS cost per mile in fuel?
The Lexus IS costs approximately 18.8p per mile in petrol at current UK prices. Over a typical commute of 30 miles per day, that is approximately £5.64 per day in fuel.
What is the WLTP MPG figure for the Lexus IS?
The official WLTP fuel economy figure for the Lexus IS is 39.2 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
Find the cheapest fuel for your IS
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