The BMW 1 Series and 3 Series represent two of the brand's most popular models, appealing to buyers seeking an engaging driving experience combined with premium quality and badge prestige. While the 1 Series serves as BMW's entry-level offering, the 3 Series sits a segment above as a more refined and upmarket proposition. In this comparison, we'll explore the key differences between these two German cars to help you make an informed decision.
The BMW 3 Series has long been regarded as the benchmark for mid-size, sporty executive cars, blending understated style, rock-solid build quality, and an upmarket image with involving driving dynamics. The 1 Series, meanwhile, aims to provide an affordable entry point into BMW ownership while retaining the brand's signature driving characteristics.
BMW 1 Series vs BMW 3 Series
Practicality
When it comes to practicality, the BMW 3 Series holds a clear edge over its smaller sibling. As a mid-size executive car, it offers more interior space and a larger boot capacity than the compact 1 Series. The 3 Series' rear seats can comfortably accommodate two tall adults, although fitting three abreast may be a squeeze due to the transmission tunnel. Its 480-litre boot (375 litres for the 330e plug-in hybrid) is on par with rivals and should suit most families, though loading can be trickier than in a hatchback.
The 1 Series, while more practical than its rear-wheel-drive predecessors, still falls behind in this department. Front-seat space is ample, but rear headroom and legroom are merely adequate for six-footers. The middle rear seat is narrow and compromised by a large floor hump. The boot capacity of 380 litres (or 300 litres in non-M135 models due to hybrid battery intrusion) is competitive for the class but lags behind the 3 Series. However, the 40/20/40 split-folding rear seats (a cost option) offer decent versatility.
Further adding to the strength of the 3 Series in this area, it is the only one of these two contenders that is also available in more practical Touring (that's 'estate' in BMW speak) body style. This not only increases the boot space 9to 500 litres), but also provides a more practical hatchback opening rather than the saloon-style tailgate on the regular 3 Series.
Driving Impressions
Both models excel in delivering the involving driving experience that BMW is renowned for, though the 3 Series arguably has the edge. Its sharp, linear steering and stiff suspension translate to precise handling and abundant grip, though the trade-off is a firm ride that can become uncomfortable on rougher roads – especially with the M Sport trim's stiffer setup.
The 1 Series, despite its switch to a front-wheel-drive layout, remains a tremendously entertaining steer that outclasses most family hatchback rivals. Its keen chassis and direct steering imbue it with an agile, pointy feel. However, the M Sport's adaptive suspension can feel overly firm at times, highlighting the 3 Series' superior damping and body control.
Both models offer a wide range of punchy turbocharged petrol and diesel engines, from the frugal yet capable entry-level units to the potent M Performance variants. The 1 Series' range-topping M135 xDrive, with its 296bhp 2.0-litre turbo petrol, is a particular highlight, delivering hot hatch thrills with a 0-62mph time of 4.9 seconds. Company car drivers might want to look to the plug-in hybrid BMW 330e as the most affordable option as far as running costs are concerned. The latest models can do around 60 miles on electric power, around double the distance of earlier versions.
Technology and Equipment
Both the 1 Series and 3 Series feature well-appointed interiors with a premium look and feel, though the larger 3 Series has the edge in overall material quality and design cohesion. The 1 Series' cabin is an impressive space, but some lower panels don't quite match the high standards set elsewhere.
BMW's iDrive infotainment system is a highlight in both models, offering a user-friendly interface with crisp graphics and logical menu layouts. However, the lack of a rotary controller in the latest generation is an ergonomic step backwards. Physical climate controls have also been replaced by touchscreen operation, further hampering ease of use.
Standard equipment levels are respectable across the range, with even base models featuring essentials like LED lights, parking sensors and a reversing camera. However, desirable features like wireless charging and adaptive cruise control often require additional option packs.
Running Costs
In terms of running costs, the smaller 1 Series has the advantage – at least for the entry-level petrol models. The 120 and 123 xDrive boast impressive official WLTP fuel economy figures of 53.2mpg and 47.9mpg respectively, thanks to their mild-hybrid systems. The range-topping M135 xDrive, being more powerful and non-hybridised, is thirstier at 37.1mpg.
The 3 Series' most frugal option is the 330e plug-in hybrid, which can achieve around 65mpg with regular charging. Among the conventional engines, the 318d diesel is the star performer at around 55mpg, while the petrol 318i and 320i should return close to 45mpg. Even the potent 330i can nudge 40mpg with careful driving.
BMW's servicing costs are higher than mainstream brands but on par with premium rivals like Audi. A three-year service plan is available for £25 per month, which can help with budgeting.
Verdict
So, how do you choose between these two BMWs? The 1 Series offers an affordable entry point into BMW ownership, delivering an engaging driving experience and premium cabin ambiance in a more compact and cost-effective package. However, it falls behind the 3 Series in terms of interior space, practicality, and outright refinement.
The 3 Series, being larger and more upmarket, provides a more well-rounded proposition – albeit at a higher price point. Its superior ride quality, roomier interior, and slightly sharper driving dynamics make it the more complete choice, despite the potential for slightly higher running costs.
If you want premium quality on a tighter budget, the 1 Series is a compelling option. But if you can stretch your budget further and need more interior space and versatility, the 3 Series remains the quintessential executive sports saloon or estate car, and still the benchmark in its class.