Mercedes-AMG A 45 S Review

The old Mercedes-AMG A 45 had one clear party trick. It was devastatingly fast in a straight line. Beyond that, it could feel one-dimensional. It was effective rather than exciting, expensive without quite feeling premium enough, and not especially lovable when the road turned twisty.

This generation fixed that. The current Mercedes-AMG A 45 S still does the fireworks-show stuff, but it is also much more rounded and much more interesting. The headline figures still make an impression. This 2.0-litre turbocharged four-cylinder produces 427PS, drives all four wheels through an eight-speed dual-clutch automatic gearbox and dispatches 0-62mph in 3.9 seconds. That was once supercar pace. In a five-door hatchback, it still feels faintly ridiculous.

More importantly, it is no longer just a point-and-squirt car. The four-wheel-drive system gives the A 45 S a more adjustable feel than older AMG hot hatches, so there is genuine enjoyment here when you are not simply chasing the next gap in traffic. It still does not serve up the last word in steering feedback, but it is far more engaging than the badge and layout might lead you to expect.

This facelifted version also benefits from the current A-Class cabin, which remains dramatic to look at and rich in technology. There are still some cheaper-feeling details if you go hunting for them, but on first impression it absolutely looks the part. For a car with this much pace, it is usefully practical too. The 370-litre boot is competitive for the class, rear space is decent by premium hatchback standards and the split-folding rear bench makes it more versatile than many two-door performance alternatives.

There is another reason the A 45 S still matters. Mercedes has already made it clear that this A-Class will not be directly replaced, which means the clock is ticking for the fastest AMG hatchback. That does not automatically make it a future classic, but it does add a bit of significance. If you want this mix of compact size, huge pace and old-school petrol performance attitude, there will not be many chances left to buy one new.

This part is simple because there is only one version to consider if you are buying new in the UK. The A 45 S now comes as an AMG Plus 4MATIC+, and that is your lot. In truth, that suits the car quite well. It is expensive, but it arrives with the right hardware and the right sense of occasion, rather than forcing you to pick through a long options list to create the version you really wanted.

That also means there is no engine decision to make. The standard A 45 disappeared from the UK line-up some time ago, so the 427PS mild-hybrid 2.0-litre turbo and eight-speed dual-clutch gearbox are all part of the package. Given how good this drivetrain is, that is no hardship. It is savagely quick, full of intent and a much better match for the chassis than a lesser engine would be.

If you are buying used, earlier A 45 S Plus cars make the most sense and remain the sweet spot. We would still avoid being distracted by the cheaper A 35 unless budget is the main concern, because that is better treated as a separate model with a different character. The A 45 S is the one that fully delivers on the badge.

The Mercedes-AMG A 45 S AMG Plus 4MATIC+ starts at £65,465, which is serious money for a hatchback. That puts it right in the firing line of the Audi RS 3 Sportback, which starts in much the same territory, and not far off cars from the class above. That is the first big hurdle with the A 45 S. You have to really want what it does, because this is no longer the sort of hot hatch you buy on a whim.

The upside is that AMG Plus trim is generously equipped, so you are not paying that headline figure for a car that still feels half-finished. Standard kit includes adaptive suspension, 19-inch alloy wheels, heated front seats, keyless entry, a Burmester sound system, augmented-reality navigation and a 360-degree camera. That goes some way towards justifying the price, even if it does not make it feel cheap.

Used values are more approachable. Early examples of this generation have now fallen to the point where the A 45 S is no longer reserved purely for brand-new buyers with deep pockets. That matters because the appeal of the car is centred on its performance, and that has not dated.

The obvious rival is the Audi RS 3 Sportback. It costs similar money, is just as quick in real-world use and has one of the great modern performance-car engines. If the noise and theatre of the powertrain matter most, the Audi still has the edge. It also feels a touch more solid inside.

The BMW M2 is not a direct rival because it is a rear-wheel-drive coupé rather than a practical hatchback, but if your budget stretches into the mid-£70,000s it becomes hard to ignore. It is less practical, less discreet and not as easy to use every day, yet it is the more focused driver’s car.

Then there is the Hyundai Ioniq 5 N. It is a very different answer to the same question, but an interesting one. It is bigger, heavier and electric, yet it delivers the kind of engineered-for-fun experience that many performance EVs still miss. If company car tax matters or you want something more left-field, it deserves a look.

Within AMG’s own range, the A 35 is cheaper but softer-edged and should be treated as a separate review. The CLA 45 S also exists for buyers who prefer a swoopier saloon or Shooting Brake shape, but the hatchback remains the most complete and most useful expression of the A 45 idea.

Like the standard A-Class, the A 45 S cabin is a bit of a mixed bag. The design is excellent. The twin-screen layout still gives the dashboard real visual drama, the turbine-style air vents look great and the driving position is spot on for a fast hatchback. The front seats are comfortable, supportive and electrically adjustable, so it is easy to settle in.

It is also pleasingly usable. Mercedes has kept proper physical climate controls, which is the sort of thing you only fully appreciate after spending time in cars that bury everything in the touchscreen. That alone makes the A 45 S easier to live with than some rivals.

Where it falls short is in the detail. Some of the glossy black trim scratches too easily, a few pieces feel lighter and creakier than they should, and overall solidity is not quite up there with the best Audi and BMW cabins. None of that ruins the experience, but it does stop the interior feeling truly exceptional.

Practicality is decent rather than outstanding. There is enough room in the front, and rear-seat space is perfectly acceptable for this class, though nobody is going to confuse it with a family estate. The boot measures 370 litres, which keeps the A 45 S competitive among premium hatchbacks. It is usefully square in shape, so it is more helpful than the figure alone suggests. Fold the rear seats and capacity rises to 1,210 litres, while the 40:20:40 split-folding arrangement is genuinely useful if you need to carry awkward loads without sacrificing all rear passenger space.

There are also a few smaller storage areas around the cabin, including a compartment under the front armrest and extra cubbies for rear passengers. So while the A 45 S is obviously bought for its performance, it does a respectable job of everyday hatchback duties too.

At 4,299mm long, 1,780mm wide and 1,433mm high, the Mercedes-AMG A 45 S is compact enough to feel manageable in town, yet broad enough to have the planted stance you want from a car like this.

It is broadly similar in footprint to other premium hot hatches, which means it is easy enough to park and easy enough to place on a narrow road, while still feeling substantial enough on a motorway. That balance is one of the car’s strengths. It never feels unwieldy.

The infotainment setup remains one of the A 45 S’s stronger points. The two 10.25-inch displays still give the cabin a properly modern look, and the MBUX system is generally quick, clear and easy enough to use once you know your way around it. The touchscreen responds cleanly and the voice control works better than many rival systems.

There is some genuinely useful functionality too. The augmented-reality navigation is more than a gimmick, overlaying directions on a live camera feed in a way that actually helps in complex junctions and unfamiliar towns. AMG Track Pace is also fitted, which will be irrelevant to many owners but is a fun extra if you plan to use the car on circuit.

Android Auto and Apple CarPlay are standard, and AMG Plus trim also brings a Burmester sound system that is well worth having. Four USB-C ports help with day-to-day usability.

Not everything is perfect. The facelift brought a steering wheel with touch-sensitive controls that are more fiddly than the older setup, and earlier cars had a touchpad controller between the seats that some buyers may actually miss. Even so, the overall impression is still strong. It feels rich in technology without becoming a chore to use.

The current A 45 S uses a mix of ARTICO man-made leather and MICROCUT microfibre as part of its standard trim, which suits the car’s sporting character well. Heated front seats are standard, and the overall look is suitably AMG-specific without becoming too garish unless you choose to make it so.

The dashboard and door trims do a good job visually, especially with the ambient lighting switched on, and there is enough contrast stitching and metallic detailing to separate the A 45 S from a regular A-Class. It feels like the fast one.

The issue is not the design or material choice so much as the execution of some smaller parts. The shinier plastics are prone to marking and a few touchpoints feel a little less substantial than they ought to in a car costing this much. The cabin still looks expensive. It just does not always feel quite as expensive as it looks.

There is one engine in the current UK line-up, and it is a memorable one. The A 45 S uses a 2.0-litre turbocharged four-cylinder mild-hybrid petrol engine with an eight-speed dual-clutch automatic gearbox and four-wheel drive. Output is 427PS and 500Nm of torque, which is enough for 0-62mph in 3.9 seconds.

That makes the car explosively quick, even by modern performance standards. It gathers speed with real violence once the drivetrain is fully on top of things, and the mid-range punch is especially impressive. It is one of those cars that can turn a short straight into an event.

Mercedes quotes a 155mph maximum speed in current UK technical data. Even if that is academic for most buyers, it gives you an idea of the sort of performance envelope you are dealing with.

The big improvement over the previous A 45 is not the pace. It is the way the car handles itself when the road turns technical. Fast all-wheel-drive performance hatchbacks used to feel very front-led when pushed hard, but the A 45 S’s torque-vectoring system gives it a much more rear-biased, adjustable feel than that. You can sense the car helping you rotate rather than simply dragging itself straight out of corners.

The steering is fast and nicely weighted, even if it does not tell you everything. More importantly, the front end bites hard and the whole car feels alert, pointy and eager. There is genuine entertainment here rather than just efficiency.

Ride quality is the compromise. The suspension is firm, and on rough British roads the A 45 S can feel a bit too tense unless you soften everything off. Comfort mode makes the best fist of daily driving, and the ability to mix softer dampers with more aggressive engine and gearbox settings is helpful. Even then, this is not a relaxed or plush hatchback. It always reminds you that it is the serious AMG one.

The engine itself is a characterful unit for a four-cylinder. There is still a hint of lag before it really detonates, but once it does, it feels savage. The exhaust note is suitably angry too, helped along a little by the speakers. It sounds good. The problem is simply that the Audi RS 3 sounds even better.

Refinement is otherwise respectable. Road noise from the tyres is noticeable, but wind and mechanical noise are well suppressed at motorway speeds, so the A 45 S is not exhausting on a long trip. For such an aggressive performance hatchback, it covers distance surprisingly well.

The A 45 S comes with the usual modern driver-assistance kit, including lane-keeping assistance, autonomous emergency braking, cruise control with limiter, traffic sign assistance and tyre-pressure monitoring. Parking is also made easier by a 360-degree camera in current AMG Plus trim.

The underlying A-Class achieved a five-star Euro NCAP rating in 2018, with strong scores for adult and child occupant protection. The important caveat is that this result is now officially marked expired by Euro NCAP because the testing protocol has moved on. That does not suddenly make the A 45 S unsafe, but it is worth knowing if you are comparing it with newer rivals carrying more recent test results.

Official combined fuel economy is 30.8 to 31.0mpg, which is not disastrous for something this quick but certainly not modest either. In gentle motorway use you might get close to the official figure. Use the performance regularly and it will drop well below that.

That is the reality of the A 45 S. It extracts huge performance from a relatively small-capacity engine, but it does not do so on a shoestring fuel budget. If you drive it the way its badge suggests, you will get to know your local petrol station quite well.

Mercedes provides a three-year vehicle warranty, along with three years of paintwork cover and a longer anti-corrosion warranty. If you want more protection after that, an extended warranty is available through Mercedes-Benz in the UK.

Servicing follows Mercedes’ usual pattern. The first service is normally due after one year or 15,500 miles, whichever comes first, and the car then alternates through the brand’s regular maintenance schedule. That is fairly typical for a premium performance hatchback, though real-world costs are unlikely to be modest if you use the car hard or wear through tyres and brakes quickly.

The current A 45 S sits in insurance group 41, which is high but not remotely surprising given the performance on offer. This is one of the areas where the running-cost reality bites hardest, especially for younger drivers or those living in high-risk postcodes.

It is the sort of car where shopping around matters. Specialist insurers may be worth a look, because the difference between quotes can be substantial.

For 2026 to 2027, the standard annual VED rate for cars like this is £200 after the first year. Because the A 45 S has a list price well above the current £40,000 threshold for petrol, hybrid and diesel cars, it is also caught by the Expensive Car Supplement. That adds a further £440 a year for five years from the start of the second licence.