Audi A3 vs A4

The A4 might be the most popular Audi sedan, but do you need one?

Audi A3 vs A4

Summary

The Audi A3 is a subcompact luxury car, whereas the Audi A4 is a compact luxury car. That means the Audi A4 has bigger dimensions and more interior room. Size differences are accompanied by subtle design differences outside and inside, and the A4 has more standard features. Performance, however, is evenly matched.

Audi sedans are a staple in the luxury car market. Smart and conservative designs complement their precision German engineering and their infotainment and driver assists are currently considered the best among German automakers.

Although America’s obsession with SUVs means the Q3 and Q5 are Audi’s best selling vehicles, the A3 and A4 are not far behind in sales. The Audi A3 is the least expensive Audi car, and often an entry point for new Audi drivers. Naturally, the A4 draws comparisons with the A3, being the next step up in the regular Audi line.

With a substantial price hike from the A3 to the A4, is the A4 really worth the extra money? Let's find out.

Price

The cheapest A3 ‘Titanium’ trim starts at $33,300, while the same trim on the A4 costs $39,100. The price difference is therefore around $6k, and relatively more costly options on the A4 can further widen that gap.

The A4 does however come with more standard features, even at the base trim. Most notable is the ‘Convenience Package’ which features keyless engine start/stop and entry, Audi side assist, aluminium window surrounds and LED interior lighting. This option costs $1,150 on the A3.

Audi A3 rear view
A3
Photo: Audi
Audi A4 rear view
A4
Photo: Audi

Design

The trademark Audi singleframe front-grille is present on both Audis, but sharper and slimmer headlights make it possible to distinguish the two cars from the front.

There are also differences at the rear. The tail lights also sport a wider, more aggressive look on the back of the A4. Meanwhile, the A4 gets two wide tailpipes on either side, whereas the A3 goes for more standard dual tailpipes on one side.

However, the most obvious difference is the shape of the cars themselves. The A4 is longer and appears more streamlined, whereas the A3 is more compact and boxy by comparison. This difference becomes even clearer when seeing them in person, as opposed to from photos.

Europeans also have access to the sportback A3 and station wagon A4 Avant, but lack of domestic love for those body types means they’re not available for the US market. Of course, if you’re looking for something similar to the A3 sportback there’s always the Volkswagen Golf which is what the A3 is based on.

Space

Since we’re comparing a compact to a subcompact car, the A4 is obviously the bigger car. But by how much?

Passengers in the front and back get an additional 2.4 inches and 1.3 inches of additional head room respectively. While the longer wheelbase surprisingly doesn’t translate into any additional legroom for passengers, passengers get over an inch of additional shoulder room.

Although both have a seating capacity of 5, the middle seat of the A4 is much better at accommodating a 5th passenger. With the A3, larger passengers will struggle to squeeze in to fill up the back row.

Audi A4 rear seats
Photo: Audi
Rear seats in the Audi A4

Comparing practicality, the A4 also has 13 cubic-feet of cargo volume, while the A3 has a cargo volume of 10 cubic-feet. Both sedans can have their rear seats folded down, giving further flexibility for carrying cargo.

Interior And Technology

Audi interiors have been the subject of much praise thanks to their most recent overhauls. They are modern, uncluttered, free from cheap materials and supported by one of the best infotainment systems around.

The differences in interior will be fairly obvious to the driver. The A3's goes with small, circular air conditioning vents, the A4 has air conditioning vents that line the entire dashboard. You also get grey oak natural wood inlays that are a touch classier than the micro-metallic silver inlays featured in the A3.

Audi A3 interior
A3
Photo: Audi
Audi A4 interior
A4
Photo: Audi

With either sedan you’ll get a 7-inch display, Apple CarPlay and Android Auto compatibility and cruise control as standard. Audi offers a host of in-car tech upgrades like a high definition Bang & Olufsen sound system, automatic climate control, 12.3-inch virtual cockpit with MMI Navigation and more.

Powertrain

Until recently, both the A3 and A4 were powered by the same 2.0-liter turbo 4-cylinder petrol engine named ‘40 TFSI’. They were tuned slightly differently, but the end result was practically the same–around 185 horsepower and capable of producing 230 lb-ft of torque.

However, Audi gave all 2021 A4 models a 12-volt mild-hybrid system which gives it a convincing performance advantage over the A3 now. Producing 201 horsepower, the latest A4 goes from 0-60 in 6.7 seconds, almost matching the much lighter A3 which takes 6.6 seconds.

Of course, if performance is critical, both sedans are also offered with the higher spec ‘45 TFSI’ engine which delivers more horsepower and torque. Going for this model also gives you a better seven-speed DSG transmission and adds Audi’s quattro all-wheel drive system, which is especially beneficial for those who will find themselves driving in harsh weather conditions.

Those wanting to get inside the sub-5 second 0-60 mph club will want to look into the S3 and S4 from the high performance Audi S range. The Audi A3 also has an RS counterpart, the RS3, which delivers the best performance of all.

Audi A3 quattro engine render
Photo: Audi

Fuel Economy

According to EPA estimates, the Audi A3 40 TFSI  gets 26/35 mpg (city/highway) and a combined gas mileage of 29 mpg. The more powerful A3 45 achieves 22/30 mpg (city/highway) and 25 mpg combined.

Despite the introduction of the mild hybrid system into the 2021 Audi A4’s powertrain, the fuel efficiency of the latest A4 has taken a hit. Down from 27/34 mpg (city/highway), the 40 TFSI A4 now only gets 24/31 mpg.

The 45 TFSI-equipped A3s and A4s are naturally less fuel efficient than their 40 TFSI counterparts.

Drive Experience

The A3’s smaller nature and lower ground clearance gives it a slightly sportier and more agile driving characteristics than the A4. This is also reflected in its slightly tighter turning diameter of 36.1 feet versus the A4’s 38.1 feet.

However, Audi’s speciality is not the sporty, thrusting and harsh driving dynamics found in BMWs or Jaguars, but a refined and comfortable ride. And in this respect, the A4 is superior to the A3. The cabin is quieter and the suspension feels softer. Overall, you get a more distinctive Audi driving experience in the A4.

Safety

The A3 and A4 were both given 5-star overall safety ratings by the National Highway Traffic Safety Administration (NHTSA) and are ‘Top Safety Picks’ according to the Insurance Institute for Highway Safety (IIHS).

However, closer inspection reveals that the A3 fared slightly better in frontal crash testing, specifically for the front passenger side, where it obtained a 5-star rating as opposed to the A4’s 4-star rating.

Moving on to safety features, Automated emergency braking and forward-collision warning come as standard on both models, but things like lane-keep assist, blind spot monitoring and high beam assist will cost extra.

Audi A3 vs A4: Verdict

The Audi A3 is a good entry-point into the German automaker, but its interior feels a notch less luxurious than the A4. The more compact size also makes for a slightly stubby exterior appearance which doesn’t look as good as the more streamlined A4.

It’s also less practical, with little room for rear-row passengers and a trunk that is limited in volume. That being said, the A4 isn’t particularly practical either, though at least rear passengers will appreciate the extra space.

While the new A4 enjoys big improvements that came in 2020 and 2021, we’re still waiting for this year’s new Audi A3. And expect noticeable improvements–they’ve been long overdue. We’ll be revisiting this comparison soon.

If you’re looking for other cars to consider in a similar price range, popular options include the Mercedes A-Class, Tesla Model 3 and BMW 2 series.