Road tests

New BMW M440i Convertible 2021 review

The switch to a fabric roof hasn’t dented the BMW M440i Convertible’s versatility

Overall Auto Express Rating

4.0 out of 5

Find your BMW 4 Series
Offers from our trusted partners on this car and its predecessors...
Or are you looking to sell your car?
9/10 sellers got the price they expected
Advertisement

Verdict

While this open-top M440i Convertible can’t match its Coupé sibling’s driving dynamics, it’s still a deeply appealing prospect that’s more involving than pretty much any other four-seat convertible at this price. Few other cabriolets manage to deliver such a strong mix of performance, handling and long-distance comfort – and in the BMW’s case it’s combined with impressive tech, too. We’ll leave the verdict on its styling up to you.

BMW has bolstered its open-top range with the new 4 Series Convertible. While most buyers choose a drop-top to enjoy open-air motoring, the most significant change to this G23 generation comes when the inevitable UK weather hits.

That’s because this new version has ditched the old car’s folding hard-top and replaced it with a fabric item. BMW argues that the complexity and packaging issues that came with that old roof are no longer worth it when a canvas top can keep the peace in the cabin just as effectively – even at speed.

The switch is a logical one because it brings plenty of benefits. For a start, the soft top is 40 per cent lighter, and perhaps more importantly it’s easier to fold away. The process takes 18 seconds, and can be done on the move at up to 31mph.

As a result, the latest 4 Series Convertible is more practical than ever. While boot space with the roof up has increased by a modest 15 litres (now 385 litres) over the old car, the significant improvement comes when it’s folded; the new model offers 300 litres, 80 more than before.

The cabin design is identical to the 4 Series Coupé’s, with the same fantastic infotainment, flawless build quality and sporty driving position. The seats gain ventilated head rests that can blow warming air on your neck on a cold roof-down outing. But it’s more cramped in the two back seats; the back rest is more upright and shoulder room is down compared with the Coupé.

Under the bonnet, the 4 Series is offered with two diesel and three petrol engines. Both diesel options each get an 11bhp mild-hybrid boost; there’s a 187bhp 420d and a 430d with 282bhp and a hefty 650Nm of torque. The petrol side of the family includes 420i and 430i models, with 181bhp and 242bhp respectively.

The 4 Series Convertible will soon be available in hot M4 form, but until then, this M440i is as potent as it gets. It produces numbers that wouldn’t have felt out of place for an M4 a couple of generations back; the 3.0-litre turbo straight-six engine makes 369bhp and 500Nm. Like the diesels, it uses mild-hybrid tech to boost fuel efficiency, but there’s also four-wheel drive as standard.

Despite that slicker roof, there’s still a significant weight gain for the open-top model. While the M440i coupé weighs 1,740kg, the convertible adds 150kg. No surprise, then, to discover that the extra mass blunts performance, too. Not that the M440i is a slouch – 0-62mph takes 0.4 seconds longer than in the coupé, but a time of 4.9 seconds is still rapid.

It’s a fantastic engine: strong, smooth and – now with the benefit of less material separating the driver from the exhaust – more tuneful than ever. It’s paired with a slick eight-speed automatic gearbox that works faultlessly when left to its own devices, and responds quickly using the steering wheel paddles.

You can feel that extra mass in corners, mind. Compared with the lighter 4 Series Coupé, the M440i Cabriolet doesn’t have the same delicate balance. What it does have is unflappable traction, great turn-in and solid body control. It’s still better to drive than any other four-seat cabrio on the market for similar money.

Despite this, it also remains a great long-distance cruiser. A controlled high-speed ride combines with great stability and that torquey engine to make for a very relaxing companion. The fabric roof does a great job of isolating road and wind noise and, with the roof down, buffeting in the front is minimal – especially with the wind deflector up. 

The Convertible costs a little over five grand more than the Coupé, so there is a sizable jump to get the open-air. The range-topping M440i costs £59,670, so it undercuts its closest rival, the Mercedes-AMG C 43 Cabriolet, which starts from £61,455. The Mercedes does have 16bhp more and is 0.1 seconds quicker from 0-62mph, but it isn’t quite as engaging to drive or any more refined.

Model:BMW M440i Convertible
Price:£59,670
Engine:3.0-litre 6cyl turbo petrol
Power/torque:369bhp/500Nm
Transmission:Eight-speed automatic, four-wheel drive 
0-62mph:4.9 seconds
Top speed:155mph
Economy:34.9mpg
CO2:182g/km
On sale:Now
Chief reviewer

Alex joined Auto Express as staff writer in early 2018, helping out with news, drives, features, and the occasional sports report. His current role of Chief reviewer sees him head up our road test team, which gives readers the full lowdown on our comparison tests.

More on 4 Series Convertible

Best used convertibles 2024
Best used convertibles - header image
Best cars & vans
12 Jan 2024

Best used convertibles 2024

If it’s open-top thrills that you’re after, the best used convertibles offer incredible value for money
New BMW M440d xDrive Convertible 2022 review
BMW M440d xDrive Convertible - front
Road tests
27 Jul 2022

New BMW M440d xDrive Convertible 2022 review

Only a very small number of UK 4 Series Convertible buyers opt for this unusual derivative, but are they missing out?
New 2021 BMW 4 Series Convertible unveiled
News
29 Sep 2020

New 2021 BMW 4 Series Convertible unveiled

The new BMW 4 Series Convertible has been officially revealed, sporting a radical grille and new folding fabric roof
BMW 4 Series Convertible - best convertibles
BMW 430i Convertible - front cornering
Features
18 Jul 2018

BMW 4 Series Convertible - best convertibles

Folding hard-top now makes 4 Series unique in the four seater convertible class
BMW 4 Series Convertible 2017 review
BMW 430i Convertible - front
Road tests
30 Jun 2017

BMW 4 Series Convertible 2017 review

The BMW 4 Series Convertible has been updated for 2017. We test it in 430i M Sport guise to see if it's improved
BMW 4 Series Convertible review
BMW 430i Convertible - front
In-depth reviews
3 Apr 2016

BMW 4 Series Convertible review

The facelifted BMW 4 Series Convertible has upped its game in terms of driving dynamics but it’s still a great cruiser
BMW M4 Convertible blasts in with 425bhp
News
16 Apr 2014

BMW M4 Convertible blasts in with 425bhp

BMW lifts the lid on its mighty new M4 Convertible in New York. It goes on sale in September for priced from £60,000
BMW 4 Series (420d) Convertible 2014 review
BMW 420d 2014 driving
Road tests
25 Feb 2014

BMW 4 Series (420d) Convertible 2014 review

We test new BMW 4 Series Convertible, which offers a relaxed drive and great engines
BMW 435i Convertible
BMW 435i Cabriolet
Road tests
18 Jan 2014

BMW 435i Convertible

New BMW 4 Series Convertible is bigger than before, but is it better? We drive top-spec 435i petrol car
BMW 4 Series Convertible revealed at LA show
BMW 4 Series Convertible at LA
News
20 Nov 2013

BMW 4 Series Convertible revealed at LA show

New BMW 4 Series Convertible has been unveiled at the LA Motor Show, priced from £35,650 - now with video
BMW 4 Series Convertible leaked
BMW 4 Series convertible leaked
News
9 Oct 2013

BMW 4 Series Convertible leaked

BMW 4 Series Convertible - official pictures have leaked online ahead of its LA show debut next month