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Audi A4 vs BMW 3 Series: which is the better used buy?

On DVSA MOT records the BMW 3 Series does better at its MOT: measured against cars of the same age, it comes out 2.6 percentage points ahead of the Audi A4 on first-time MOT passes. That comparison covers 73,614 real tests across every generation on the road, not a survey. A pass with rectification at the station counts as a pass here, and as a failure in DVSA's own initial-test measure. The MOT checks safety and emissions items, not the engine, clutch or gearbox, so this is one measure of how each car holds up rather than a full reliability verdict; the common faults below cover the rest.

MOT first-time pass rate

Counted from DVSA’s anonymised MOT test records. “vs age-matched” compares each model against what the national fleet scores at the same age — the only fair better-or-worse number, because an older fleet fails more whatever its build quality.

Audi A4
Pass rate77.3%
Age-matched national75.0%
Difference+2.3
Tests24,990
BMW 3 Series
Pass rate79.9%
Age-matched national75.1%
Difference+4.9
Tests48,624

These figures count every generation still on the road, not only the one described below: mostly Audi A4s registered 2003–2022 and BMW 3 Series registered 1999–2022.

Source: DVSA MOT Anonymised Data 2025 (Open Government Licence v3.0). National first-time pass rate 77.3%. Class 4 tests in Great Britain, test type NT (a normal annual test), retests excluded. A pass, or a pass with rectification at the station, counts as a first-time pass; DVSA's own initial-test measure counts a rectified pass as a failure and so reports a lower figure. Testing in Northern Ireland is run separately by the DVA under its own rules. The difference is worked out before rounding, so it can be 0.1 away from the two rounded figures beside it.

Audi A4

B9 (2015–2023) · D-segment executive saloon and Avant estate. One of the most popular used premium cars in the UK alongside the BMW 3 Series. Available as saloon and Avant estate. Key engines: 2.0 TFSI petrol (150–252 PS), 2.0 TDI diesel (136–190 PS), 35 TFSI mild hybrid (150 PS), 40 TFSI (190 PS), 40 TDI (204 PS).

The Audi A4 B9 is a premium, refined executive car with strong build quality, but it requires disciplined Audi specialist maintenance to keep running costs manageable. The 2.0 TDI diesel is reliable on motorway mileage but has documented timing belt (not chain) service requirements — belt failure on the B9 2.0 TDI is an engine-write-off event. The 2.0 TFSI mild hybrid (post-2019) is the better choice for mixed UK driving. Avoid any B9 A4 without full documented service history — Audi's repair costs are high and an unmaintained A4 can quickly become very expensive.

What goes wrong

  • Safety recall R/2020/138recall
    Moisture may enter the belt-driven starter-alternator
    34,982 vehicles in the whole recall (DVSA’s figure for every model it covers) · built between 1 June 2017 and 31 March 2020
    Large recall — 34,982 vehicles. Check a car by registration on GOV.UK.
  • Safety recall R/2020/265recall
    Moisture may enter the belt driven starter-alternator
    11,936 vehicles in the whole recall (DVSA’s figure for every model it covers) · built between 10 August 2018 and 11 March 2020
    Large recall — 11,936 vehicles. Check a car by registration on GOV.UK.
  • 2.0 TDI timing belt service (interference engine)critical
    No audible warning — belt failure is sudden and catastrophic. Prevention through scheduled service is the only protection.
    All B9 A4 2.0 TDI (2015–2023) · Audi recommended interval: every 80,000 miles or 4 years (whichever first). Many specialists recommend 55,000 miles or 4 years in UK stop-start conditions. · £700–£1,200 timing belt kit (preventive); £8,000–£15,000+ engine replacement if belt fails (the 2.0 TDI is an interference engine — belt failure destroys the engine)
    Check: Ask for documented timing belt replacement history. If the car is at 55,000+ miles with no record of a belt change, factor the service into the purchase price or walk away. The 2.0 TDI's timing belt is one of the most important pre-purchase checks on any B9 A4. The 2.0 TFSI petrol uses a timing chain, but the pre-facelift 1.4 TFSI has a toothed belt too, so ask for its belt history as well.
  • MMI infotainment and virtual cockpit freezingminor
    MMI screen freeze; navigation crash; virtual cockpit going blank; MMI reboot loops
    2015–2019 (older MMI generations) · Not mileage-related — software degradation over time · £0 — software update at Audi dealer; hardware replacement £600–£1,200 if MMI control unit fails
    Check: Test all MMI functions during the test drive — navigation, Bluetooth, media, climate control (which is MMI-integrated on many trims). Ask if the latest Audi software update has been applied. Most MMI issues are software-related and resolved by an update.
Typical asking price:
£6,495–£18,995, median £11,495 (middle 80% and median, cars on Autoza on 29 October 2026)
Fuel economy:
49–57 mpg (2.0 TDI real-world UK motorway mixed); 38–47 mpg (35 TFSI MHEV real-world)
Vehicle tax:
£200/year standard rate from the second year, hybrids included — the alternative-fuel discount ended on 1 April 2025. A car registered from April 2017 with a list price over £40,000 when new adds the £440/year Expensive Car Supplement in years 2–6 (£640 in all). Cars registered 2001–2017 pay a CO2 band, roughly £20–£790/year (2026/27 rates).
Best years:
2020, 2021
Years to avoid:
2015
Used Audi A4s for saleFull A4 fault guideUsed Audis

Also compare:

BMW 3 Series

F30 (2012–2019) / G20 (2019–present) · D-segment executive saloon and touring estate. The most popular used premium car in the UK by volume. Available in a wide range of engines: 316i, 318i, 320i, 330i petrols; 316d, 318d, 320d, 330d diesels; 330e plug-in hybrid. Saloon, Touring (estate), and Gran Turismo body styles.

The BMW 3 Series (F30 2012–2019, G20 2019-on) rewards disciplined maintenance. On the pre-2015 N47 diesel, owners report the rear-mounted timing chain failing, an engine-out repair, so ask for chain history. The B47 diesel and B48 petrol that followed from 2015 are much better regarded. Full BMW-dealer or specialist service history is essential.

What goes wrong

  • Safety recall R/2022/255recall
    Undetected EGR System leaks may cause thermal activity in the intake manifold
    322,745 vehicles in the whole recall (DVSA’s figure for every model it covers) · built between 3 December 2014 and 12 July 2021
    Large recall — 322,745 vehicles. Check a car by registration on GOV.UK.
  • Safety recall R/2022/206recall
    The exhaust gas recirculation cooler may leak over time and cause thermal incident
    319,399 vehicles in the whole recall (DVSA’s figure for every model it covers) · built between 9 December 2011 and 4 June 2019
    Large recall — 319,399 vehicles. Check a car by registration on GOV.UK.
  • N47 diesel timing chain failure (F30 2012–2015)critical
    Chain rattle on cold start; rattling from rear of engine; engine management light; in severe cases, sudden engine failure
    F30 2012–2015 with N47 diesel (316d, 318d, 320d) · From 60,000 miles; can occur earlier if oil changes were delayed · £3,000–£6,000 timing chain replacement (rear-mounted chain requires engine removal); up to £10,000+ if the chain has jumped and damaged the engine
    Check: This is the single most critical check on any F30 N47 diesel. The N47 chain is rear-mounted — listen for chain rattle at idle with the bonnet up. Ask for proof of timing chain replacement in the service history. If the chain has not been replaced and the car has over 75,000 miles, budget for the repair or walk away. The B47 diesel (post-2015 on the F30 facelift and all G20) is unaffected.
  • Electric water pump failure (N20/B46/B48 petrols)major
    Coolant warning light; engine overheating; steam from engine bay; loss of heat from heater
    F30 2012–2019 petrol models (N20 engine) · From 50,000 miles; often fails between 60,000–95,000 miles · £600–£1,200 water pump replacement
    Check: Check coolant level and condition. Ask about any history of overheating or coolant warning lights. The electric water pump on N20 engines is a known maintenance item — not catastrophic if caught early, but a failed pump can cause overheating if ignored. Budget for proactive replacement on high-mileage N20 cars.
Typical asking price:
£5,295–£19,999, median £10,995 (middle 80% and median, cars on Autoza on 29 October 2026)
Fuel economy:
47–57 mpg (320d real-world UK mixed motorway); 35–44 mpg (320i petrol real-world)
Vehicle tax:
£200/year standard rate from the second year, hybrids included — the alternative-fuel discount ended on 1 April 2025. A car registered from April 2017 with a list price over £40,000 when new adds the £440/year Expensive Car Supplement in years 2–6 (£640 in all). Cars registered 2001–2017 pay a CO2 band, roughly £20–£790/year (2026/27 rates).
Best years:
2019, 2020
Years to avoid:
2012
Used BMW 3 Series for saleFull 3 Series fault guideUsed BMWs

Also compare:

Which one suits you

Audi A4

Good for: Executive-segment buyers who want a refined, well-built premium saloon or estate. Motorway commuters (A4 Avant TDI is excellent value for high-mileage motorway use). Buyers who will use an Audi specialist for servicing.

Less good for: Buyers who cannot verify the 2.0 TDI timing belt service history. S-Tronic automatic buyers without gearbox oil-service history above 40,000 miles. Buyers wanting the lowest total cost of ownership — a Skoda Superb or Skoda Octavia diesel estate offers broadly similar space and refinement for significantly lower running costs.

BMW 3 Series

Good for: Buyers who want a genuine driver's car and are prepared to maintain it properly. Motorway-mile buyers who will use the 320d's diesel efficiency on long UK commutes. Buyers with a BMW specialist garage lined up for servicing.

Less good for: Buyers who want the lowest total cost of ownership — a Toyota Corolla or Skoda Octavia will cost meaningfully less to run. F30 N47 diesel buyers without verified timing chain history — this is a potentially catastrophic repair. First-time BMW buyers who plan to service it at the cheapest possible garage — BMW models require BMW-specific knowledge and fluids.

Frequently Asked Questions

Which is more reliable, the Audi A4 or the BMW 3 Series?
On the MOT measure, the BMW 3 Series: measured against cars of the same age, it comes out 2.6 percentage points ahead of the Audi A4 on first-time MOT passes, across 73,614 DVSA-recorded tests covering every generation on the road. A pass with rectification at the station counts as a pass here, and as a failure in DVSA's own initial-test measure. The MOT checks safety and emissions items, not the engine, clutch or gearbox, so this is one measure of how each car holds up rather than a full reliability verdict.
How do the MOT pass rates of the Audi A4 and the BMW 3 Series compare?
77.3% of Audi A4s pass their MOT first time (24,990 tests in DVSA's records) and 79.9% of BMW 3 Series pass their MOT first time (48,624 tests). The national first-time rate is 77.3%, but cars of the Audi A4's age average 75.0% and cars of the BMW 3 Series's age 75.1% — so the Audi A4 runs 2.3 points better than its age group and the BMW 3 Series runs 4.9 points better than its own. A pass with rectification at the station counts as a pass here, and as a failure in DVSA's own initial-test measure.
Which years of the Audi A4 and BMW 3 Series should I avoid?
Audi A4: 2015–2016 B9 launch cars: more reported MMI infotainment issues, some ZF gearbox calibration complaints on early DSG/S-Tronic automatics, and earlier fuel system issues on the 2.0 TDI before production revisions. The DVSA MOT table on this page rates 2016 registrations above all cars registered that year, so it is not named as a year to avoid. BMW 3 Series: 2012–2014 F30 with N47 diesel: the N47 2.0-litre diesel used in 316d, 318d, and 320d had a rear-mounted timing chain that stretched and failed prematurely, often at 60,000–95,000 miles. The repair requires removing the engine — costs of £3,000–£6,000 were common. Many N47 engines were replaced under extended warranty or goodwill; survivors without documented chain replacement are high-risk. The DVSA MOT table on this page rates 2013 and 2014 registrations above all cars registered those years, so they are not named as years to avoid.
Is the Audi A4 or the BMW 3 Series cheaper to run?
On fuel the two are too close to call: the most economical versions return up to 57 mpg (Audi A4) and 57 mpg (BMW 3 Series), on the figures in our model guides. For cars registered from April 2017, vehicle tax works the same way for both: the £200/year standard rate from the second year, hybrids included, plus the £440/year Expensive Car Supplement in years 2–6 on a car that listed at over £40,000 new — the price when new, not what you pay for it used. Any Audi A4 or BMW 3 Series registered between 1 March 2001 and 31 March 2017 pays a CO2 band instead, roughly £20–£790/year (2026/27 rates). Insurance differs mainly by driver and postcode rather than by model, so treat any model-level insurance figure with caution.

MOT figures are counted from DVSA records and are the only measured statistic here. Prices, economy and tax bands are indicative and vary by specification, condition and where the car has lived. Last reviewed: 2026-10-06 / 2026-10-06.