The 2015 Lexus IS 350 C gets 22 MPG combined. This hardtop convertible emphasizes stylish design and open-air driving rather than maximum fuel efficiency. It’s not trying to be a Prius; it offers a luxury experience for drivers who enjoy a convertible top and the sound of a V6 engine.

City and highway performance

The EPA estimates the IS 350 C will get 19 MPG in the city and 27 MPG on the highway. Stop-and-go traffic causes the naturally aspirated 3.5L V6 to work harder, reducing fuel economy. More relaxed cruising at higher speeds allows the six-speed automatic transmission to use its highest gear, improving fuel economy. The difference between city and highway MPG suggests the IS 350 C is better suited for longer drives, which is a plus for top-down weekend trips. Drivers who mainly drive in the city will likely see gas mileage closer to 19 MPG.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2015 Lexus IS 350 C at $2,650. This calculation is based on driving 15,000 miles per year, a combination of city and highway driving, and average national gas prices. This is a helpful estimate, but your actual fuel costs will change based on your driving and local gas prices. Watching your fuel consumption can give you a more precise idea of what you’re spending.

Real-world expectations

Official EPA estimates are a standard measurement, but the real-world fuel economy of the 2015 Lexus IS 350 C greatly depends on driving habits and conditions. Accelerating quickly and braking hard will lower fuel efficiency. However, gently pressing the accelerator and predicting traffic to keep a consistent speed can help you get close to, or even exceed, the EPA’s highway estimates. Checking tire pressure and keeping up with maintenance can also help improve gas mileage. The IS 350 C isn’t made for economical commuting, but careful driving can still help.

How it compares

The IS 350 C’s fuel economy is about average compared to other luxury convertibles of its time. For example, the BMW 428i Convertible, which has a turbocharged four-cylinder engine, has a combined EPA rating of 27 MPG. This gets better gas mileage, but doesn’t have the naturally aspirated six-cylinder smoothness and sound of the IS 350 C. The Infiniti Q60 Convertible has a similar engine setup to the Lexus but has a slightly lower fuel economy rating of around 21 MPG combined. Consider the Mercedes-Benz E350 Cabriolet from the same year, which is rated at 23 MPG combined, offering similar gas mileage to the IS. Looking at all Lexus fuel economy data, the IS 350 C’s fuel consumption is similar to other Lexus models that put performance and luxury before maximum efficiency. See the IS MPG across all years.

Tips to maximize efficiency

The IS 350 C’s six-speed automatic transmission has a “Snow” mode, which softens the accelerator response and reduces wheelspin. While it’s made for slippery conditions, you can also use it in normal driving to promote smoother acceleration and save gas, especially in stop-and-go traffic.

Make sure to regularly check and keep the tire pressure at the recommended level. Tires that don’t have enough air create more rolling resistance. This makes the engine work harder, which uses more gas. The correct tire pressure is on a sticker inside the driver’s side doorjamb.

Avoid accelerating quickly and braking hard if possible. The IS 350 C’s V6 engine responds fast to the accelerator, but using only the power you need will greatly improve fuel economy. Anticipate traffic and keep a steady speed to waste less gas.

Think about the weight you’re carrying. Getting rid of unneeded items from the trunk and passenger area can lower the car’s overall weight, leading to small gains in fuel economy. Even a little bit helps, especially on long trips.

Maintain your car. Make sure the air filter is replaced and get regular oil changes using the correct type of synthetic oil. A clean air filter lets the engine breathe easier, and fresh synthetic oil lowers friction and improves overall efficiency.