Infiniti Q50 vs Lexus IS

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.

2015–2024

Infiniti Q50

Midsize Cars · 60 configurations

31mpg combined (best)
All Infiniti Q50 specs

2015–2026

Lexus IS

Compact Cars · 52 configurations

26mpg combined (best)
All Lexus IS specs

Head-to-head specifications

MetricInfiniti Q50Lexus IS
Best combined MPG31 mpg26 mpg
Best city MPG29 mpg22 mpg
Best highway MPG36 mpg32 mpg
Lowest annual fuel costEPA estimate at 15,000 miles per year$2,450$2,900
Lowest CO2 output286 g/mi345 g/mi
Engines offeredSIDI, 3.5, 2.0, 3.7SIDI & PFI, SIDI
TransmissionsAutomatic (S7)Automatic (S6), Automatic (S8)
DrivetrainsAll-Wheel Drive, Rear-Wheel DriveAll-Wheel Drive, Rear-Wheel Drive
Fuel typesPremiumPremium
EPA classMidsize CarsCompact Cars
Years covered2015–20242015–2026
Configurations on record6052

Source: EPA fuel economy records via fueleconomy.gov. Best-case values across all recorded configurations for each model.

Q50 vs IS: common questions

Which is better on gas, the Infiniti Q50 or the Lexus IS?

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 Q50 and IS offer?

Infiniti Q50: SIDI, 3.5, 2.0, 3.7. Lexus IS: SIDI & PFI, SIDI.

Are they in the same vehicle class?

The EPA classifies the Infiniti Q50 as Midsize Cars and the Lexus IS as Compact Cars, so they aren't a like-for-like match on size.

More Q50 comparisons

Comparison id: infiniti-q50-vs-lexus-is