Cost to own
BMW M340i Ownership Costs UK
Around £715 per month to own
The BMW M340i is one of the most appealing used performance saloons in the UK. It gives you much of the speed and refinement of a full M car, but with lower running costs, better comfort and everyday usability. The 3.0-litre B58 engine is strong, smooth and seriously quick, but ownership costs are still much higher than a normal 3 Series once fuel, insurance, tyres, servicing and depreciation are included.
Estimated annual ownership cost
Assumptions used
- 8,000 miles per year
- 3 years ownership
- Petrol at £1.50/litre
- Depreciation based on age, mileage, usage and car type
Is the BMW M340i expensive to run?
A BMW M340i is likely to cost around £715 per month over 3 years, based on 8,000 miles per year. The biggest costs are usually depreciation, insurance, fuel and maintenance.
Calculate your own M340i costsBMW M340i ownership cost breakdown
Fuel costs
Fuel is one of the main day-to-day costs of running a BMW M340i. The B58 engine can be surprisingly efficient on a steady motorway run, but this is still a 3.0-litre turbocharged petrol car with strong performance. Short trips, cold starts, town driving and regular hard acceleration will all increase fuel spend quickly. For buyers covering high annual mileage, fuel costs can become one of the biggest parts of ownership.
Insurance costs
Insurance for a BMW M340i is usually much higher than for a regular 320i or 320d. The car’s performance, value, repair costs and desirability all affect premiums. Younger drivers, city postcodes and modified cars are likely to see noticeably higher quotes. Before buying, insurance should be checked properly rather than estimated, because it can make a big difference to the real monthly ownership cost.
Maintenance costs
Maintenance costs for a BMW M340i are higher than a normal 3 Series, but usually lower than a full M car. Tyres, brakes, servicing and repair buffers need to be taken seriously. Premium tyres are important on a powerful rear-wheel-drive or xDrive performance saloon, and brake components can be expensive if they need replacing. A well-maintained car with strong service history is usually worth paying more for.
Depreciation
Depreciation is one of the biggest hidden costs of owning a BMW M340i. Although desirable performance BMWs can hold value better than ordinary models, the M340i is still a relatively expensive car and can lose thousands of pounds over a few years. Mileage, age, condition, specification and market demand all affect resale value. Buyers should consider the total cost of ownership, not just the monthly finance payment.
Is the BMW M340i reliable?
The BMW M340i has a strong reputation for reliability compared with many other modern performance cars. A large part of that comes from the B58 3.0-litre turbocharged six-cylinder engine, which is generally seen as one of BMW's strongest modern engines. It is smooth, powerful and capable of high mileage when serviced correctly. That does not mean every M340i is automatically a safe buy. Maintenance history still matters. A well-serviced example with regular oil changes, quality tyres and evidence of proper care is much more appealing than a cheaper car with missing history or poor upkeep. The M340i is also a performance car, so wear items cost more than they would on a basic 3 Series. Tyres, brakes, suspension components and fluids should all be factored into the ownership budget. Overall, the M340i is one of the better choices if you want serious performance without moving into the higher running costs of an M3. The key is buying a good example and budgeting like it is a performance car, not a normal saloon.
Real-world fuel economy
Real-world fuel economy in a BMW M340i depends heavily on driving style. On long motorway journeys, the M340i can be surprisingly efficient for the performance it offers, with careful drivers often seeing figures in the mid-to-high 30s mpg range. Around town, fuel economy drops quickly. Short journeys, traffic, cold starts and regular acceleration can bring the figure down into the 20s. If the car is used mainly for commuting in stop-start traffic, fuel costs will be noticeably higher than the official figures suggest. The M340i sits in an interesting position. It can be a comfortable long-distance car that returns respectable motorway economy, but it can also drink fuel quickly when driven hard. This is why annual mileage and driving style make such a big difference to the total ownership cost. For buyers doing mostly motorway miles, the fuel cost may be easier to justify. For buyers doing lots of short trips, a diesel 330d or 320d may be much cheaper to run.
Common ownership costs
The main BMW M340i ownership costs to budget for are tyres, brakes, servicing, insurance and depreciation. Tyres are especially important because the car has a lot of power and needs quality rubber to perform properly. Cheap tyres can ruin the way the car drives and reduce confidence in wet conditions. Brakes can also become expensive, especially if the car has been driven hard or used regularly on fast roads. Pads and discs are normal wear items, but they cost more than they would on a regular family car. Servicing is generally manageable for a performance BMW, but it should not be ignored. Oil services, filters, brake fluid, spark plugs and other routine items all add up over time. As the car ages, owners should also budget for batteries, suspension wear and occasional repairs. The M340i is not ruinously expensive for what it offers, but it is still a premium performance car. The cheapest examples can become expensive if previous owners have skipped maintenance.
Should you buy a BMW M340i?
The BMW M340i is a very strong choice for someone who wants one car that can do almost everything. It is fast, comfortable, practical, refined and usable every day. For many buyers, it offers the best balance between performance and real-world ownership costs in the 3 Series range. It makes the most sense if you want strong performance but do not want the higher insurance, servicing and tyre costs of an M3. It also works well for drivers who cover long journeys and want something more exciting than a diesel saloon. However, it is not the cheapest 3 Series to own. Fuel, insurance, tyres and depreciation all need to be considered before buying. A 320d or 330d will usually be cheaper to run, while an M3 will be more exciting but more expensive again. For many UK buyers, the M340i is the sweet spot. The important thing is to buy on condition and history, not just price, and to understand the real monthly cost before committing.
Calculate your own M340i costsBMW M340i running costs FAQs
Is a BMW M340i expensive to run?
Yes, a BMW M340i is more expensive to run than a normal 3 Series because of fuel, insurance, tyres, servicing and depreciation. It is usually cheaper to own than a full BMW M3, though.
What MPG does a BMW M340i get?
Real-world fuel economy depends on driving style. Motorway driving can return respectable figures, but town driving and hard acceleration can quickly reduce MPG.
Is the BMW M340i reliable?
The BMW M340i is generally considered reliable when maintained properly, mainly thanks to the strong B58 engine. Service history and condition are still very important when buying used.