Lexus IS vs Infiniti Q50
The Infiniti Q50 is the more efficient of the two: it reaches 31 mpg combined versus 26 mpg for the Lexus IS, a 5 mpg advantage and costs about $450 less per year to fuel.
Across 5 measured categories, the Infiniti Q50 leads in 5. Figures are EPA test data, not manufacturer claims.
Head-to-head specifications
| Metric | Lexus IS | Infiniti Q50 |
|---|---|---|
| Best combined MPG | 26 mpg | 31 mpg ✓ |
| Best city MPG | 22 mpg | 29 mpg ✓ |
| Best highway MPG | 32 mpg | 36 mpg ✓ |
| Lowest annual fuel costEPA estimate at 15,000 miles per year | $2,900 | $2,450 ✓ |
| Lowest CO2 output | 345 g/mi | 286 g/mi ✓ |
| Engines offered | SIDI & PFI, SIDI | SIDI, 3.5, 2.0, 3.7 |
| Transmissions | Automatic (S6), Automatic (S8) | Automatic (S7) |
| Drivetrains | All-Wheel Drive, Rear-Wheel Drive | All-Wheel Drive, Rear-Wheel Drive |
| Fuel types | Premium | Premium |
| EPA class | Compact Cars | Midsize Cars |
| Years covered | 2015–2026 | 2015–2024 |
| Configurations on record | 52 | 60 |
Source: EPA fuel economy records via fueleconomy.gov. Best-case values across all recorded configurations for each model.
IS vs Q50: common questions
Which is better on gas, the Lexus IS or the Infiniti Q50?
The Infiniti Q50 is the more efficient of the two: it reaches 31 mpg combined versus 26 mpg for the Lexus IS, a 5 mpg advantage and costs about $450 less per year to fuel.
Which costs less to run per year?
By EPA estimates at 15,000 miles a year, the Infiniti Q50 runs about $2,450 a year in fuel at its most efficient configuration, versus about $2,900 for the Lexus IS — a difference of roughly $450 per year.
What engines do the IS and Q50 offer?
Lexus IS: SIDI & PFI, SIDI. Infiniti Q50: SIDI, 3.5, 2.0, 3.7.
Are they in the same vehicle class?
The EPA classifies the Lexus IS as Compact Cars and the Infiniti Q50 as Midsize Cars, so they aren't a like-for-like match on size.
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Comparison id: lexus-is-vs-infiniti-q50