The BMW 330i is the better fit if you want a comfortable daily driver with lower running costs, while the BMW 340i suits you if straight-line speed and a smoother six-cylinder engine matter more. The core difference is power: the 330i has a 2.0-litre four-cylinder with 255 hp, and the 340i has a 3.0-litre inline-six with 382 hp.
Which Numbers Fit Your Driving Needs?
Both cars share the same body, the same cabin and the same 8-speed automatic gearbox, so the engine and price are what separate them. Everything else on this list follows from those two facts.
| Feature | BMW 330i | BMW 340i |
|---|---|---|
| Engine | 2.0-litre turbo four-cylinder | 3.0-litre turbo inline-six |
| Power | 255 hp | 382 hp |
| Torque | 295 lb-ft | 369 lb-ft |
| 0–60 mph | about 5.6 seconds | about 4.4 seconds |
| Fuel economy (combined) | around 29 mpg | around 26 mpg |
| Drivetrain | RWD or xDrive AWD | RWD or xDrive AWD |
| Price | lower | several thousand dollars more |
BMW publishes the official figures for both cars on its 3 Series Sedan page, so check there before you buy — exact output and mpg can shift slightly between model years and drivetrain choices.
How Different Do They Feel to Drive?
The 330i feels quick enough for everyday driving and never feels underpowered in town or on the highway. The 340i feels like a different class of car: the six-cylinder pulls hard from low revs, overtakes happen almost instantly, and the engine note is noticeably smoother and deeper.
Tip: Drive both back-to-back on the same road before deciding. The 340i’s acceleration is the one thing no spec sheet fully prepares you for — and the main reason people stretch their budget.
Is the 340i Worth the Extra Money?
Yes, if you value performance and plan to keep the car for years. The extra cost buys you roughly 127 more horsepower and a 1.2-second quicker run to 60 mph. That’s a genuine upgrade for enthusiasts.
But money spent on power you don’t use is money wasted. If those are why you’re shopping a 3 Series at all, the 340i adds cost, not usefulness.
Which One Should You Actually Buy?
Choose the 330i if:
- You drive mostly in city traffic or commute daily, where you rarely use more than half the 330i’s power anyway.
- Fuel costs and insurance matter to your monthly budget.
- You’re buying used and want the widest choice of cars at a lower price point.
Choose the 340i if:
- You regularly drive on fast roads or long routes and want effortless overtaking.
- You care about engine smoothness and sound, not just speed.
- You plan to keep the car a long time and the higher running costs don’t worry you.
One more option worth knowing: the M340i sits above the 340i with even more power and sportier tuning. If you test a 340i and still want more, that’s the next step — but it’s also a bigger jump in price.
What About Running Costs and Reliability?
The 330i is cheaper to run on every count: it uses less fuel and its four-cylinder engine is the most common 3 Series engine, so parts are easy to find. The 340i’s inline-six (the B58 engine) has a strong reputation for reliability, but fixes cost six-cylinder prices.
Frequently Asked Questions
Is the 340i faster than the 330i?
Yes, clearly. The 340i reaches 60 mph in about 4.4 seconds against the 330i’s roughly 5.6 seconds, and it pulls noticeably harder at any speed.
Do the 330i and 340i look different?
Only slightly. Both share the same body and dimensions, with the 340i carrying small visual touches like different wheels, badging and exhaust tips. From a distance, most people can’t tell them apart — the difference is what you feel from the driver’s seat, not what you see.
Is the 340i expensive to insure?
Usually somewhat more than the 330i, because insurers price in the higher power and value. The exact gap depends on your age, location and driving record, so get quotes for both specific models before you buy — the difference varies a lot between drivers.
Can a 330i be tuned to match a 340i?
Not really. If you want the 340i’s performance, buying the 340i is the safer and usually smarter route than modifying a four-cylinder.
Which holds its value better?
Both hold value similarly well, but the 340i’s rarer engine can help it on the used market among enthusiasts.
Conclusion
Start by test-driving the 330i, then the 340i on the same day. If the six-cylinder’s power feels like something you’d genuinely use every week, pay for it — if the 330i already feels like enough, you’ve just saved yourself a meaningful amount of money and a higher fuel bill.
