DecodedCarsAudi S8 vs BMW 5 Series
2026 Audi S8 vs 2026 BMW 5 Series — two rivals compared on efficiency, size, safety and reliability.
The short version
The BMW 5 Series is more fuel-efficient: 31 vs 18 MPG combined in its best version.
That works out to about $1,900 a year less in fuel for the BMW 5 Series (EPA estimate, 15,000 miles).
The Audi S8 is the bigger car, about 5 inches longer.
Across all model years since 2005, the BMW 5 Series has had fewer recall campaigns (9 vs 16).
The two cars
The 2026 Audi S8 is a large car offered with a 4.0L 8-cyl turbo engine, including a hybrid version and all-wheel drive. It measures about 204 inches long and 77 inches wide on a 118-inch wheelbase, with a curb weight of roughly 5,313 lb.
The 2026 BMW 5 Series is a midsize car offered with 2 engines (2.0L 4-cyl turbo and 3.0L 6-cyl turbo), including a hybrid version and rear-wheel drive and all-wheel drive. It measures about 199 inches long and 75 inches wide on a 118-inch wheelbase, with a curb weight of roughly 4,158 lb (5-Series 530i Xdrive 4dr Sedan).
Buying used? The 2024 S8 and the 2024 5 Series have the fewest problems in our data; avoid the 2021 S8.
Basics
Efficiency
Performance & space
Safety & reliability
Interest
Green = clearly better. Prices are not included. How we calculate this →
Which one should you choose?
Choose the Audi S8 if…
- You want more room (5 in longer)
Choose the BMW 5 Series if…
- You want lower fuel bills (31 vs 18 MPG)
- You want something easier to park (5 in shorter)
- You put reliability history first (9 vs 16 recalls since 2005)
Pros & cons of each
2026 Audi S8
- Hybrid version availableOffered as a hybrid as well as gas.
- Below-average fuel economyBest version gets 18 MPG combined, 31% below the 2026 large car average of 25.9 MPG.
- Premium fuel requiredEvery gasoline version is rated for premium, which raises running costs.
2026 BMW 5 Series
- Hybrid version availableOffered as a hybrid and plug-in hybrid as well as gas.
- AWD / 4WD available
- Premium fuel requiredEvery gasoline version is rated for premium, which raises running costs.
Full 2026 Audi S8 specs →Full 2026 BMW 5 Series specs →Compare fuel costs for your driving →Compare size & garage fit →