The 2015 Buick Regal eAssist, with its 2.4L 4-cylinder engine, gets a combined 28 MPG. This is a respectable number that reflects a balance between mid-size sedan comfort and lower fuel costs, appealing to buyers who value a touch of luxury without sacrificing efficiency for their daily commute.

City and highway performance

Breaking down the 28 MPG combined figure, the Regal eAssist achieves an EPA-estimated 24 MPG in the city. This figure is realistic for suburban environments and stop-and-go traffic. The smooth-shifting 6-speed automatic transmission paired with the electric assist system works efficiently to minimize fuel consumption at lower speeds. On the highway, the car stretches its legs to achieve 35 MPG. This is where the eAssist system truly shines, providing a small electric boost and regenerative braking to maximize fuel savings during long, steady-state drives. The highway figure makes it a viable option for frequent commuters or those who take regular road trips, reducing the fuel costs typically associated with a car of this size.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2015 Buick Regal eAssist at exactly $1,550. This figure is calculated based on driving 15,000 miles per year, using the national average fuel price for regular gasoline at the time of the calculation. While fluctuating gas prices mean this figure can vary, it offers a consistent benchmark for comparing the Regal eAssist to other vehicles in its segment. For budget-conscious buyers this is critical. The $1,550 figure directly influences long-term ownership costs and makes the Regal eAssist attractive compared to less eco-focused rivals.

Real-world expectations

While the EPA estimates provide a standardized benchmark, real-world MPG can vary depending on driving habits, road conditions, and maintenance. Aggressive acceleration, frequent braking, and neglecting routine maintenance can all negatively impact fuel economy. Owners who prioritize smooth, consistent driving, adhere to recommended service intervals, and properly inflate their tires will likely find their real-world MPG closer to the EPA estimates. The eAssist system’s effectiveness is also impacted by driving style – gentle driving will yield greater gains from regenerative braking.

How it compares

Consider the 2015 Toyota Camry Hybrid. It gets a combined 41 MPG, which significantly eclipses the Regal eAssist. The Camry Hybrid prioritizes fuel efficiency above all else. Conversely, the 2015 Acura TLX with its 2.4L engine achieves around 28 MPG combined. The Regal offers an equivalent MPG with a more luxurious experience for some drivers. Looking at the Honda Accord Hybrid from the same year gets you around 47 MPG combined. For the target buyer of the Regal eAssist these comparisons are meaningful.

They want some semblance of luxury. The Buick’s fuel economy is secondary, provided that the ownership experience is worth their money. See all Buick fuel economy data here.

Tips to maximize efficiency

Pay close attention to tire pressure. The Regal eAssist’s fuel efficiency benefits significantly from properly inflated tires. Keep tires inflated to the recommended pressure listed on the sticker inside the driver’s side door jamb. Underinflated tires increase rolling resistance, leading to reduced fuel economy. Check pressure regularly, especially during temperature fluctuations that can impact tire pressure.

Use cruise control on the highway. Maintaining a consistent speed minimizes unnecessary acceleration and deceleration, allowing the eAssist system to operate at its most efficient. Using cruise control on long highway stretches helps optimize fuel economy and reduces driver fatigue. Avoid aggressive acceleration and braking, as these actions will drain the available energy.

Avoid unnecessary idling. Modern engines don’t require extended warm-up periods, so avoid idling for prolonged periods, especially in cold weather. Turn off the engine when stopped for more than a few seconds. Excessive idling wastes fuel and contributes to unnecessary emissions.

Consider the grade of gasoline. Despite recommendations, some owners experiment with higher octane fuels, hoping to improve performance or fuel economy. The 2015 Regal eAssist is designed to operate on regular unleaded gasoline, and using premium fuel will not provide any discernible benefit to fuel economy. Stick to the manufacturer’s recommendation and save money at the pump.

Keep your car well maintained. Regular maintenance, including oil changes, air filter replacements, and spark plug maintenance, plays an important role in maintaining optimal fuel economy. A well-maintained engine operates more efficiently, maximizing fuel mileage. Neglecting maintenance will lead to reduced efficiency. See REGAL MPG across all years.