Where each one leads
Audi A8
- Against cars of the same age, the Audi A8 comes out better at its first MOT test (passes 24% more often than average) than the Mercedes-Benz S-Class (passes 16% more often than average).
- New Audi A8 cars registered in Europe in 2022 average 161 g/km of CO₂ on the WLTP test, against 165 for the Mercedes-Benz S-Class in 2022.
Mercedes-Benz S-Class
- Against cars of the same year, the Mercedes-Benz S-Class comes out better in New York safety inspections (fails 64% less often than average) than the Audi A8 (fails 31% less often than average).
- Fewer Mercedes-Benz S-Class cars in the Netherlands carry an illogical odometer record (8.2% against 9.8%).
- Measured by the cars' own fuel meters, the diesel hybrid Mercedes-Benz S-Class uses 8.2 l/100 km on the road, the Audi A8 8.5.
Too close to call: real-world fuel use in Europe, petrol hybrid (l/100 km).
Only measures that do not depend on how many cars were sold: pass and failure rates against cars of the same age, ratings, fuel use and CO₂. How we compare
At a glance
| Audi A8 | Mercedes-Benz S-Class | |
|---|---|---|
| Model years in the US safety record | 1995–2026 | 1994–2012 |
| New cars registered in Europe | 58,589 (2010–2022) | 136,729 (2010–2022) |
| Licensed in the United Kingdom | 9,740 | 22,797 |
| On the road in the Netherlands | 2,149 | 8,416 |
| In traffic in Finland | 747 | 2,778 |
EEA new-car registrations (CC BY 4.0) · DVLA licensed vehicles (OGL v3.0) · RDW (CC0) · Traficom (CC BY 4.0) · generations: Wikidata (CC0).
Reliability and problems
| Audi A8 | Mercedes-Benz S-Class | |
|---|---|---|
| UK MOT first-time pass rate | 87% | 83% |
| … against cars of the same age | +24% | +16% |
| New York safety inspections failed | 1.6% | 0.6% |
| … against cars of the same year | −31% | −64% |
| Illogical odometer records (NL) | 9.8% | 8.2% |
| US owner complaints | 252 | 271 |
| Most complaints about | Engine | Electrical system |
| Model year with most complaints | 2013 (49) | 2000 (81) |
| US recall campaigns | 31 | 11 |
| Manufacturer service bulletins | 15,324 | 116 |
| NHTSA defect investigations | 8 | 7 |
Complaint, recall and bulletin counts grow with the number of cars sold and are not adjusted for it. UK MOT: DVSA anonymised MOT results (OGL v3.0); New York: DMV inspections; complaints, recalls, bulletins and investigations: NHTSA (public domain); odometer: RDW (CC0).
Fuel, emissions and price
| Audi A8 | Mercedes-Benz S-Class | |
|---|---|---|
| Official combined fuel use, Canada | 10.9 l/100 km (2026) | — |
| Real-world use in Europe, diesel hybrid | 8.5 l/100 km | 8.2 l/100 km |
| Real-world use in Europe, petrol hybrid | 11.9 l/100 km | 11.9 l/100 km |
| Real-world use in Europe, diesel | — | 8.8 l/100 km |
| Real-world use in Europe, petrol | — | 15.6 l/100 km |
| Official CO₂ of new cars in Europe | 161 g/km | 165 g/km |
| Average power of new cars in Europe | 238 kW (319 hp) | 290 kW (389 hp) |
| Average mass in running order | 2,184 kg | 2,204 kg |
| Dutch list price when new (median) | €132,661 | €142,880 |
| Average odometer in Finland | 253,000 km | 226,000 km |
Canada: NRCan Fuel Consumption Ratings, most frugal version of the latest year (OGL Canada). Europe: EEA monitoring of new-car CO₂ and on-board fuel meters (OBFCM), CC BY 4.0. Price: RDW catalogue price (CC0). Finland: Traficom (CC BY 4.0).