Autoblog and Yahoo may earn commission from links in this article.With Audi having recently replaced its A4 and A5 range with a single new A5 model, we thought it was the perfect time to see how the new generation model stacks up to the old guard. The naming choice may be a bit confusing, as the new A5 is a four-door liftback (just like the old A5 Sportback) but Audi calls it a sedan. It's really an amalgamation of the best features of the old four-door A5 and the traditional four-door A4 sedan, which is the main thing.As of 2026 there are no A5 coupes or convertibles, and with EV models now being given even numbering, the A4 will return, but as an all-electric model only. There. If you weren't mystified by Audi's numbering change already, then this explanation should certainly have done it.AdvertisementAdvertisementWhatever the new A5 body style may be called, the point is that it is a versatile and stylish new compact err, sedan. But so was the old A4, and in S trim it was rather good. So, let's see whether the new A5 has moved the game on enough to make it the better choice.Audi S4 (2025)AudiView the 2 images of this gallery on the original articleIt may still look modern, but the B9 generation Audi sedan was first introduced way back in 2015 as a 2016 model year offering. The US got the A4 a year later, with the spicy S4 model arriving in 2018. A facelift in 2020 as well as several other upgrades over its production lifecycle kept this model competitive with newer rivals, and a 349-hp 3.0-liter turbocharged V6 engine paired with an eight-speed automatic transmission and all-wheel drive was standard on the S4 for all model years.AudiView the 2 images of this gallery on the original articleAdvertisementAdvertisementAudi claimed a 4.4-second 0-60 mph time, which is still competitive in this class today, and when we tested it a few years back, we found the handling to be predictable and sure-footed. The overall impression was of an understated sports sedan that went about its business without making a big deal about. Textbook Audi. The interior was well-crafted, too, and had a level of fit and finish you'd expect from a car that could be optioned up to nearly $70,000.2020 and newer models got a 10.1-inch infotainment touchscreen, while a digital instrument cluster was standard from the beginning. Aside from the demure exterior styling and overly quiet exhaust note, the only real criticism of the S4 was that its 13.0-cubic-foot trunk was a little on the small side. The mechanically identical previous gen S5 Sportback offered 22 cubic feet of cargo space in comparison, but its swooping roofline impinged on rear passenger headroom.Audi S5 (2026)AudiView the 2 images of this gallery on the original articleThe all-new Audi S5 introduced in 2025 retains the Sportback layout of the previous generation four-door A5 models, although Audi insists that it is actually a sedan. The rear end does look a little more stepped than the old car, but it is still a liftback which is a good thing for both practicality and cargo space.AdvertisementAdvertisementUnder the hood sits an upgraded 3.0-liter turbocharged V6 engine paired with a 48-volt mild-hybrid system, producing 362 horsepower and sending power to all four wheels through a seven-speed dual clutch transmission. The exterior is more evolution than revolution, but the interior certainly looks far more modern.AudiView the 2 images of this gallery on the original articleA 11.9-inch digital instrument cluster and a 14.5-inch center touchscreen dominate the dashboard, and a 10.9-inch front passenger display is also available. While power and torque figures are up, the new S5 is just 0.1 seconds quicker to 60mph than the older S4. The outgoing S5 did the 0-60mph sprint in 4.5-seconds for reference.In terms of the behind-the-wheel experience, the new model is even more composed when pushed hard and comes standard with a sport rear differential. The body-hugging front seats keep you in place when taking corners with enthusiasm, and the overall feel you get is that this is a very capable and unflappable performance sedan.Audi S4 and S5 Side-by-Side ComparisonView the 2 images of this gallery on the original article2025 Audi S42026 Audi S5Body Style4-Door Sedan4-Door Liftback SedanEngine3.0L Turbocharged V63.0L Turbo V6 + 48V Mild HybridPower349 hp362 hpTorque369 lb-ft406 lb-ftTransmission8-Speed Automatic7-Speed Dual-Clutch Automatic0–60 mph4.4 sec4.3 secFuel Economy (EPA)24 MPG Combined (20 City / 29 Hwy)23 MPG Combined (20 City / 29 Hwy)Pricing / MSRP$46,000 – $52,000 (Average used price)$54,900 base MSRP in 2024$63,300 starting base MSRP in 2026Front Row Headroom37.3 in40.0 inFront Row Legroom41.3 in41.0 inSecond Row Headroom37.4 in37.2 inSecond Row Legroom35.7 in36.1 inCargo Space13.0 cubic feet (Trunk)22.6 cu ft behind 2nd row / 37.5 cu ft rear seats folded(Note: Prices exclude destination charges, options, and local taxes.)2025 Audi S4 vs. 2026 Audi S5: Pricing ComparisonJames RiswickStarting at $63,300, the 2026 Audi S5 is well-priced compared to its direct rivals from BMW and Mercedes. A 386-hp BMW M440i xDrive Gran Coupe starts at $67,100, the BMW M340i xDrive sedan version is $64,300, while the 416-hp Mercedes AMG C 43 sedan is slightly pricier at $64,150. Factor in a few options, perhaps a bump up in trim and the obligatory destination charges and taxes, and you can easily add between $5,000 to $10,000 onto these figures.AdvertisementAdvertisementRealistically speaking, a 2026 Audi S5 equipped with the mid-spec Premium Plus trim and the Technology Package will cost $69,095 including the $1,295 destination charge. For reference, the base S5 in Premium trim is $64,595 including destination.The original base MSRP for a 2025 Audi S4 started at $54,900, with preowned 2024 and 2025 models now hovering between $45,000 and $52,000, depending on mileage and trim (Premium Plus vs. Prestige). The older S5 went out of production in 2024 and was around $3,000 more overall than the S4 when new.Used examples are also selling used for similar prices. The bottom line is that a lightly used 2025 S4 offers a massive value proposition, saving buyers anywhere from $13,000 to over $24,000 compared to a new 2026 model year S5. Factor in the steep depreciation new cars suffer, and going used has never looked so appealing.2025 Audi S4 or 2026 Audi S5?AudiThe new S5 moves the game on in every single way. It is more practical and spacious (even than the old S5 Sportback), comes with the latest in standard and optional tech, has more composed handling and is a little quicker and more efficient than before. You also get the benefit of a new car warranty and the latest passive and active safety features.AdvertisementAdvertisementHowever, when examining the bare performance figures, drawing on memories of our previous drives, and considering the massive potential savings on offer, the previous generation Audi S4 comes out of this matchup looking better than ever. It may never have been the most aggressive or quickest offering in its class, but its depth of capabilities and overall competence makes it hard to ignore.If the limited cargo space is a dealbreaker, then the more practical previous gen S5 is ready to step in. Both of these models offer great value and should still be covered by the original Audi warranty for a few more years. Whether you go new or used, there isn't a bad decision to be made here.This story was originally published by Autoblog on Aug 2, 2026, where it first appeared in the Features section. Add Autoblog as a Preferred Source by clicking here.