21 MPG combined won’t win any fuel economy awards, but the RX 350 L isn’t designed for thrift. It’s a stretched version of Lexus’ popular RX SUV, adding a third row of seats for occasional use. Buyers prioritize Lexus’ reputation for bulletproof reliability, a quiet cabin, and smooth power delivery over squeezing every last mile from a gallon of premium fuel.

City and highway performance

The EPA estimates that the RX 350 L AWD gets 18 MPG in the city and 25 MPG on the highway. The V6’s ample torque helps it accelerate smoothly from a standstill, but stop-and-go traffic inevitably takes a toll on fuel economy. On the open road, the eight-speed automatic transmission helps keep the engine in its sweet spot. Though 25 MPG on the highway is achievable, expect closer to 22-23 MPG if you’re frequently passing or driving at higher speeds. The RX 350 L encourages a relaxed driving style; attempting to rush it will only diminish its efficiency.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2021 Lexus RX 350 L AWD at $2,100. This figure is based on driving 15,000 miles per year and using the national average fuel price. Of course, your actual expenditure will depend on your driving habits, the type of driving you do, and the prevailing fuel prices in your area. For example, owners who primarily drive in the city will likely exceed the $2,100 estimate. Don’t take this as financial advice; you should adjust your own budget accordingly.

Real-world expectations

While the EPA estimates provide a standardized benchmark, real-world MPG can vary significantly. Owners report figures anywhere from 19 MPG to 24 MPG combined, depending on their driving conditions and habits. Consistent highway driving at moderate speeds is the key to achieving the higher end of that range. Short trips, aggressive acceleration, and cold weather will all contribute to lower fuel economy. Tire pressure is also important in fuel economy. Keep your tires properly inflated to maximize efficiency.

How it compares

The RX 350 L’s fuel economy trails some of its competitors. For example, the Acura MDX (non-hybrid) achieves a combined 22 MPG, while the Infiniti QX60 rates at 23 MPG. Even the Volvo XC90 B6, with its turbocharged and supercharged engine, manages 22 MPG combined. Buyers in this segment prioritize luxury, safety, and reliability, areas where Lexus consistently scores well. The hybrid RX 450h L offers considerably better fuel economy (29 MPG combined), but at a higher price point and compromised cargo space due to the battery pack. For those prioritizing space and Lexus luxury over outright fuel savings, it remains a good choice. See RX MPG across all years here.

Tips to maximize efficiency

Don’t accelerate hard from stop lights. The RX 350 L’s engine is powerful enough to provide smooth acceleration without needing to push it hard. A lighter foot on the accelerator pedal will make a noticeable difference over time, especially in city driving.

Maintain a steady speed on the highway. Using cruise control, when appropriate, helps to minimize unnecessary speed fluctuations that waste fuel. Avoiding sudden acceleration and braking can also help.

Ensure your tires are properly inflated. Underinflated tires increase rolling resistance, which reduces fuel economy. Check your tire pressure regularly and inflate them to the pressure specified on the door jamb sticker.

Reduce unnecessary weight. Carrying extra cargo in the vehicle adds weight, forcing the engine to work harder. Remove any items you don’t need to improve fuel efficiency, and be mindful with heavier loads.

Consider the RX 450h L. You’re stuck with the RX body, but and the hybrid RX provides significantly better fuel economy at some practical cost. See all Lexus fuel economy data.