27 MPG combined is fine for the 2018 BMW 230i Convertible. BMW knows nobody buys this car to save gas. It’s a small, rear-wheel-drive convertible designed for sunny weekend drives and looking good. The 2.0L turbocharged four-cylinder offers enough power, and the eight-speed automatic is smooth and responsive, making this car more about grand touring than efficiency.

City and highway performance

The EPA estimates for the 2018 230i Convertible are 24 MPG in the city and 34 MPG on the highway. The lower city figure is due to stop-and-go driving, which uses more fuel. The turbocharger has to spool up more often, and the engine idles more. The 34 MPG highway figure is achievable on long road trips at consistent speeds, but expect it to drop if you accelerate often to pass or drive fast. The 230i is made to be enjoyed, and that often means using the engine’s power. See 230I MPG across all years to see how the 2018 model compares.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2018 BMW 230i Convertible at $2,150. This is based on driving 15,000 miles per year, with a mix of city and highway driving, and using the national average fuel price. This helps compare running costs of different vehicles, but your fuel expenses will depend on your driving, location, and fuel prices. If you drive much more or less than 15,000 miles a year, or live where fuel costs more, your annual fuel bill will differ from $2,150.

Real-world expectations

EPA estimates are a baseline, but real-world MPG for the 2018 BMW 230i Convertible will probably be slightly below 27 MPG. The EPA tests are done in controlled labs. Aggressive driving, frequent short trips, and using the air conditioning all hurt fuel economy. Owners who drive carefully to save fuel can probably match or beat the EPA estimates, but most drivers of this vehicle likely won’t focus only on maximizing MPG. The EPA figures are a best-case scenario under ideal conditions.

How it compares

The 2018 BMW 230i Convertible is in a small group of cars. The Mazda MX-5 Miata, a competitor in terms of fun, gets a combined 30 MPG with its automatic transmission. The Miata focuses on light weight and open-air driving rather than luxury, while the BMW is more premium. The Audi A3 Cabriolet, with its 2.0T engine offering a combined 29 MPG, is another choice, with a similar mix of efficiency and luxury, though some feel it’s less sporty than the 230i. Even a Mini Cooper S Convertible with a combined 26 MPG shows the trade-offs. The Mini is quirky and handles well, but the BMW is more substantial and refined. Be sure to compare all Bmw fuel economy data.

Tips to maximize efficiency

Use premium fuel, as BMW recommends. The 2.0L turbocharged engine works best on higher octane gasoline, which can improve fuel economy and performance. While it might be tempting to save money with regular fuel, it could reduce your MPG.

Avoid hard acceleration. The turbocharger gives plenty of power, but each quick acceleration uses more fuel. Drive smoothly and gradually to use less fuel. Watch traffic and keep a steady speed when you can.

Keep your tires inflated. Under-inflated tires increase rolling resistance, which reduces fuel efficiency. Check your tire pressure often and inflate them to the recommended pressure on the sticker inside the driver’s side door.

Remove extra weight. Carrying extra weight in your car reduces fuel economy. Remove any unnecessary items from your trunk and passenger areas to lighten the load.

Don’t idle. Idling uses fuel without going anywhere. If you’re stopped for more than a minute, turn off the engine to save fuel. Modern engines restart quickly and efficiently, so restarting uses less fuel than idling.