Costs, insurance groups, MPG and CO2
Broadly speaking, the 3 Series is priced between the slightly cheaper equivalent Audi A4 and the slightly more expensive Mercedes C Class. Resale values are predicted to be quite strong by class standards, so, if you're buying privately, you can expect your 3 Series to have retained a greater chunk of its value than most competitors after three years.
The cheapest version for company car drivers is the 330e hybrid; CO2 emissions of as low as 37g/km keep it in the lower benefit-in-kind (BIK) tax bands. The 318d will feature on many company car lists, as will the 320d, but both incur a 4% diesel surcharge due to not being RDE2 compliant. In fact, with both occupying the same BIK tax bracket, upgrading to a 320d looks all the more tempting. It proves very economical in real-world driving, averaging 47.2 mpg in our True MPG tests.
To get the best economy out of the plug-in hybrid 330e you need to keep the battery charged, because otherwise you’re basically running on its 2.0-litre petrol engine alone. Predictably, while the M340i offers the best performance, it also returns the worst fuel economy.
Equipment, options and extras
Mid-range Sport trim is our favourite. As well as coming with sportier bumpers and 18in alloy wheels, it also brings those all-important leather seats that are heated in the front. These are added to the usual 3 Series equipment, which includes three-zone climate control (with a separate controller for rear passengers), cruise control, heated front seats, power-folding door mirrors and automatic lights and wipers. Add the aforementioned infotainment features and visibility aids and you have a well-equipped car.
However, people clearly appreciate sporty looks: most BMW buyers opt for the even more aggressive-looking M Sport trim. We wouldn’t necessarily endorse this, because it doesn’t give you a whole lot more than added style for your money, but if this is your thing, we'd recommend driving before you buy. To reiterate what we said earlier, M Sport models have rather a firm ride, so you might want to consider replacing the default M Sport suspension with the optional adaptive M suspension. Admittedly, this comes as part of a pricey M Sport Plus Package – although it’s standard on the excellent M340i.
In the 2019 What Car? Reliability Survey, BMW finished in the bottom third of the table, above Jaguar and Mercedes, but below Audi and many non-premium brands such as Skoda. The latest 3 Series has yet to appear in our survey, though.
BMW provides a three-year warranty with no mileage cap – relatively impressive for the class as other cars have a mileage limit. You can also extend the 3 Series’ warranty for an extra cost if you intend to keep the car longer. The 330e plug-in hybrid has cover for the battery extended to six years (capped at 60,000 miles between years three and six)
Safety and security
The 3 Series landed a five-star rating from safety experts Euro NCAP, and achieved highly impressive scores in each specific area that was tested. The organisation has made its tests more stringent recently and the A4 and C Class were tested too long ago to compare fairly against the 3 Series, but it outscored the Volvo S60.
All versions of the 3 Series come with a healthy roster of active safety systems that are designed to prevent you having a bump and passive ones to protect you if you do. The list includes automatic emergency braking (AEB) that looks out for pedestrians as well as cars, lane departure warning and traffic sign recognition.
The optional Driving Assistant Plus pack further reduces your chances of an incident with the addition of lane-keeping assistance, blindspot monitoring and cross-traffic alert, which warns if you’re about to pull out of a side junction into the path of an oncoming car.
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