Two significantly similar cars, no doubt about that. Still, each one has something different to offer. Having both cars powered by diesel engines and utilizing the 5-door wagon body style within the same 'Large family car' segment, the only major difference here really is their wheel drive configuration (rear for the BMW and front in the case of the Audi). The first one has a BMW-engineered powertrain under the hood, a 4-cylinder, 16-valves 122hp unit, while the other one gets its power and torque from a 4-cylinder, 16-valves 140hp engine designed by Volkswagen.

Both vehicles got tested by European New Car Assessment Programme (Euro NCAP), with the BMW being a slightly better choice apparently. That aside, let's consider some other aspects which affect safety. Both vehicles belong to the large family car segment, which is generally a good thing safety-wise, but that fact doesn't break the tie between the two cars. Furthermore, taking kerb weight as an important factor into account, 3 Series offers a marginal difference of 1% more metal.

Reliability is not the best thing to consider on the make level, but it is worth mentioning that both brands display similar results in faults and breakdowns, at least on all of the models level. These are the official statistics, while our visitors describe reliability of BMW with an average rating of 4.1, and models under the Audi badge with 4.2 out of 5. Some independent research have also placed 3 Series 21% below average, and A4 9% below the first one. That apart, owners of different cars powered by the same engine as 3 Series rank it on average as 4.8, while the one under the competitor's bonnet gets 4.3 out of 5.

Audi is undoubtly more agile, reaching 100km/h in 1 seconds less than its competitor. In addition to that it accelerates all the way to 207 kilometers per hour, 3km/h more than the other car. When it comes to fuel economy things look pretty much the same for both cars, averaging around 5.8 liters of fuel per 100 kilometers (49 mpg), in combined cycle.

BMW appears just a bit more reliable, although the difference is truly marginal. The most important thing when deciding between any two vehicles should always be safety, both passive and active. In my opinion, everything taken into account, 3 Series offers much better overall protection, which launches it ahead of the other contender. From there things take a different direction, with Audi outracing its opponent in any situation possible, making it better choice for boy racers. Fuel consumption is more or less the same. It's really tough to make a final decision here, but if I'd need to, I'd say BMW. In any case that's my personal view, built upon all the data available to me. What should decide here though is the way you feel about the two vehicles, and I hope you'll find my guidelines useful in the process. I suggest you spend two more minutes in order to find out which car, based on your needs and budget, would be picked by the virtual adviser™, among more than 12.000 different ones in our database.