2025 head-to-head · Subcompact Car
2025 BMW 8 Series vs Mercedes-Benz SL-Class Plug-in Hybrid
MPG, range and what each one really costs you to fuel, from official EPA ratings and recalculated with your own gas and electricity prices.
AWD · 4.0L 8-cyl turbo · 9-speed automatic · 29 MPGe + 18 MPG
The 2025 BMW 8 Series is the cheaper one to run. Driving 15,000 miles a year with $3.95/gal premium gas and 18¢/kWh electricity, it costs about $2,469 a year to fuel (24 MPG), versus $2,770 for the 2025 Mercedes-Benz SL-Class Plug-in Hybrid (29 MPGe + 18 MPG). That's roughly $301 a year, or about $1,505 over five years.
Your numbers
Change these to match your driving and local prices. Every figure and chart on this page updates.
Fuel cost over 10 years
- BMW 8 Series
- Mercedes-Benz SL-Class Plug-in Hybrid
Side by side
| BMW 8 Series | Mercedes-Benz SL-Class Plug-in Hybrid | |
|---|---|---|
| $2,469 | Your annual fuel cost | $2,770 |
| 24 MPG | Combined efficiency | 29 MPGe + 18 MPG |
| 21 MPG | City | 33 MPGe / 16 MPG |
| 29 MPG | Highway | 25 MPGe / 22 MPG |
| — | Electricity use (kWh/100 mi) | 43 kWh |
| — | Driving range | 350 mi |
| — | All-electric range | 11 mi |
| 81 cu ft | Passenger volume | 76 cu ft |
| 15 cu ft | Cargo volume | 2 cu ft |
| 368 g/mi | Tailpipe CO₂ (g/mi) | 379 g/mi |
| 5/10 | EPA fuel economy score | 4/10 |
| 5/10 | EPA greenhouse gas score | 5/10 |
| — | Charge time at 240V | 1.1 hrs |
| Gas | Powertrain | Plug-in hybrid |
| Premium gasoline | Fuel | Premium gas + electricity |
| 3.0L 6-cyl turbo | Engine / motor | 4.0L 8-cyl turbo |
| 8-speed automatic | Transmission | 9-speed automatic |
| RWD | Drivetrain | AWD |
✓ marks the better value. EPA scores run 1–10 (10 is best). Volumes come from the EPA interior volume index and aren't published for every body style.
BMW 8 Series vs Mercedes-Benz SL-Class Plug-in Hybrid across model years
- BMW 8 Series
- Mercedes-Benz SL-Class Plug-in Hybrid
Annual fuel cost of the most efficient configuration of each model year, at your prices. Click a point to open that year.
How they differ
Per EPA interior volume figures, the BMW 8 Series has more passenger space (81 vs. 76 cu ft); the BMW 8 Series has more cargo space (15 vs. 2 cu ft).
Among 30 2025 subcompact cars, the BMW 8 Series ranks 17th and the Mercedes-Benz SL-Class Plug-in Hybrid 22nd for lowest fuel cost.
The powertrains differ: the BMW 8 Series is a conventional gas model, while the Mercedes-Benz SL-Class Plug-in Hybrid is a plug-in hybrid.
Frequently asked questions
Which is more fuel-efficient, the 2025 BMW 8 Series or the 2025 Mercedes-Benz SL-Class Plug-in Hybrid?
Measured by cost to drive, the BMW 8 Series. The BMW 8 Series is rated 24 MPG combined and the Mercedes-Benz SL-Class Plug-in Hybrid 29 MPGe + 18 MPG (EPA, most efficient configuration of each).
How much does it cost to fuel the 2025 BMW 8 Series vs. the Mercedes-Benz SL-Class Plug-in Hybrid per year?
At 15,000 miles a year with $3.95/gal premium gas and 18¢/kWh electricity, about $2,469 for the BMW 8 Series and $2,770 for the Mercedes-Benz SL-Class Plug-in Hybrid.
Which has more cargo space?
The BMW 8 Series, with 15 cu ft of luggage volume versus 2 cu ft (EPA interior volume index).
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