In-depth reviews

BMW 4 Series Convertible review

The BMW 4 Series Convertible is one of the best four-seater soft-tops around

Carbuyer Rating

4.2 out of 5

Price
£40,380 - £54,350

Pros

  • Good to drive
  • Comfortable on long trips
  • New soft-top roof is just as quiet as previous hard-top model

Cons

  • Not as much fun as the 4 Series coupe
  • Expensive
  • Rear seats aren’t very roomy

The BMW 4 Series Convertible is the soft-top model in the 4 Series range, which in turn is the two-door version of the 3 Series. The 3 Series and 4 Series feature many of the same engines and share many parts, despite the fact that they look very different from the outside.

The main difference is the 4 Series’ huge grille. Whether you love or hate it is up to you, but to our eyes it’s certainly bolder and more eye-catching than the styling of its competitors: the Mercedes C-Class Cabriolet and Audi A5 Cabriolet.

The latest 4 Series Convertible gets a fabric roof. The previous version used a folding hard top, but BMW says that new roof technology means the soft-top is just as quiet when it’s up, but it’s lighter and you get more boot space. That holds true In our experience – the new roof isn’t just good for those things, but it’s also quicker to fold away (it takes 18 seconds to do so).

The interior of the 4 Series Convertible is very similar to that of the coupe, which means it’s packed with the latest tech and has high-quality materials that make it feel very upmarket – but you would expect that because the price is higher than ever. We particularly like the driving position, which is sporty and comfortable, and the fact that it’s still fairly quiet on the move even with the roof down.

There are plenty of engines to choose from, including three petrol and two diesels. The diesels are the 420d and 430d, offering 187bhp and 282bhp respectively, while the petrol options are the 420i, 430i and M440i. These provide 181bhp, 242bhp and 369bhp respectively and are smooth, punchy and fun to use.

The 4 Series is more fun to drive than its Mercedes and Audi alternatives, yet it also works really well as a comfortable cruiser. There aren’t that many four-seat convertibles available these days, so your choice is quite limited – but if that’s what you’re after, the new 4 Series Convertible should be on your shortlist.

MPG, running costs & CO2

High-powered petrol models are thirsty, but the diesels are good for motorways

In general, convertible cars aren’t known for their fuel economy. In fact, since they are usually heavier than hard-top models (they require extra strengthening because of the soft roof), convertibles are generally more expensive to run than coupes – and that’s true with the 4 Series, although it’s not by a huge amount.

The range starts with the 420i model, which has a 2.0-litre petrol engine. It returns 41.5mpg and emits 154g/km of CO2, so it’s a good all-rounder. The 420d diesel is more economical, at 57.6mpg and 129g/km of CO2, but it’s a bit noisier and isn’t great for local trips.

The larger engines are the 430i and 430d, and these return 40.4mpg and 52.3mpg. The best reason to choose these engines is not fuel economy but because they are smoother and more powerful than the four-cylinder engines.

The M440i model is one for enthusiasts because it’s the fastest car in the range – it returns 35.3mpg and emits 182g/km of CO2, which are reasonable for the performance on offer, but it’s quite expensive to run. 

Engines, drive & performance

The M440i is the driver’s choice but all models are good to drive

The M440i is the model to go for if you are a keen driver and don’t mind the running costs, because it features tweaked suspension to make it more fun to drive – it’s more enjoyable than a Mercedes-AMG C43 Cabriolet in corners and it can go from 0-62mph in just 4.9 seconds, so it has plenty of performance.

That’s thanks to a six-cylinder engine with 369bhp, so it also sounds great with the roof down and it has a slick and fast-shifting eight-speed automatic gearbox. Despite its racy performance the M440i is comfortable on long trips – and that’s true of all models because the soft-top roof provides a good amount of sound-deadening and there’s not too much buffeting from the wind with it down, either.

The 4 Series has a comfortable suspension set-up that deals with bumps well. If you’re just cruising, one of the other models will be a better choice - the 420i has 181bhp and the 430i has 242bhp, so both have plenty of performance. If you do a lot of motorway trips, the 187bhp 420d is a good option, while the powerful 430d model is fun if you don’t mind the slightly more gruff noise it makes over the 430i petrol.

The 4 Series Convertible is the best four-seat convertible to drive at this kind of budget.

Interior & comfort

The new soft-top 4 Series is just as quiet as the old hard-top version

The new soft-top roof replaces a folding hard-top that was on the previous 4 Series Convertible, but it’s just as quiet inside with the roof up, and the car is lighter overall. It’s quicker to take down – it takes 18 seconds at up to 31mph – and there’s a bigger boot as a result.

The interior is taken from the 4 Series coupe and that means it’s excellent – the materials are high quality, the seats are comfortable and there’s lots of tech on board. There are extras here, too, including optional vents on the headrests designed to keep your neck warm with the roof down in cold weather.

The infotainment is the same as in the 4 Series coupe, which means it’s easy to use, looks modern and has lots of useful features. There are online services for the sat-nav, a simple dial-based control system and a screen in place of traditional dials behind the wheel, which can display sat-nav directions and more. It’s all very smart and works well.

Practicality & boot space

As with most four-seater soft-tops, rear-seat space is limited

The new soft-top roof means there’s more room in the back of this version of the 4 Series Convertible. There’s now 385 litres of boot space, which is about the same as in an average family hatchback – although there are only 300 litres when the roof is down, because it is stored above the luggage area when folded away.

This means the 4 Series Convertible isn’t as practical as the Audi A5 Cabriolet, but it’s still reasonable for a convertible car. The rear seats are a little cramped, as with many cars of this type; adults won’t want to sit there for too long because legroom is limited. With the roof up there’s not as much space as in the 4 Series coupe and the seats are more upright.

Reliability & safety

The 4 Series is based on tried-and-tested components

The 4 Series is too new to be featured in the Driver Power customer satisfaction survey, but it’s clear that BMW has some work to do to impress its customers – it was ranked 27th out of 30 car makers in 2020. 

However, the 4 Series Convertible uses engines and other parts from the 3 Series saloon, so parts availability is good and the engines are tried-and-tested in these other models. The 3 Series scored well in its Euro NCAP crash test, which bodes well for the 4 Series, which may not get a test of its own.

Standard safety kit includes Active Guard Plus, which adds lane departure warning, autonomous emergency braking and front collision warning. You also get parking assist with sensors and a rear-view camera.

Next Steps

Which Is Best?

Cheapest

  • Name
    420i Sport 2dr Auto [Business Media]
  • Gearbox type
    Semi-auto
  • Price
    £40,380

Most Economical

  • Name
    420d MHT M Sport 2dr Step Auto
  • Gearbox type
    Semi-auto
  • Price
    £47,020

Fastest

  • Name
    435d xDrive M Sport 2dr Auto [Professional Media]
  • Gearbox type
    Semi-auto
  • Price
    £52,360

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