BMW 3 Series vs Audi A4: Compare by Reg (2026)
Side-by-side comparison of the BMW 3 Series and Audi A4, covering MOT pass rates, estimated running costs, typical issues, and overall reliability. Based on 1,297,627 MOT tests (DVSA MOT data for tests in 2024, retests included).
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This page shows model-level MOT data. For the exact BMW 3 Series and Audi A4 you are viewing, enter a reg plate below for its MOT history, mileage checks and running costs.
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Quick Verdict
This is a very close comparison. The BMW 3 Series and Audi A4 both have an 83% MOT pass rate, so they are evenly matched on MOT results. Your decision should come down to the condition of the actual car, running costs, and which feels better to drive.
BMW 3 Series
83%
MOT pass rate
806,092 tests
Audi A4
83%
MOT pass rate
491,535 tests
Full Comparison: BMW 3 Series vs Audi A4
| Category | BMW 3 Series | Audi A4 |
|---|---|---|
| MOT Pass Rate | 83% | 83% |
| MOT Fail Rate | 17% | 17% |
| vs All-Model Avg | +1 pts | +1 pts |
| Est. Fuel Cost (petrol, 8,000 mi/yr) | £1,817 | £1,817 |
| Est. Insurance Group | 25-35 | 25-35 |
| Est. Depreciation/yr | £2,000-£3,500 | £2,000-£3,500 |
| Engine Size | 2.2L | 2.1L |
| Fuel Type(s) | Petrol, Diesel | Diesel, Petrol |
| Segment | Premium | Premium |
| Avg Mileage | 105,806 miWinner | 120,108 mi |
| MOT Tests Analysed | 806,092 | 491,535 |
| Model Years | 32 years | 27 years |
| Best Year | 2021 (93%) | 2021 (96%)Winner |
| Worst Year | 2000 (77%)Winner | 1995 (61%) |
| Reliability Trend | Improving | Improving |
Pass rates are the share of MOT tests that ended in a pass (DVSA MOT data for tests in 2024, retests included), across all years of each model. Best and worst years need at least 100 tests. Fuel cost, insurance group and depreciation are our rough estimates from engine size and make, not official figures.
Common Problems Comparison
Typical issues to check on cars of this type and age, not faults measured for these models.
BMW 3 Series: Typical Issues to Check
- •DPF and emissions issues (diesel models)
- •Higher tyre and brake wear (larger engine)
- •Suspension wear on older models
- •Lighting defects (common on all cars)
Audi A4: Typical Issues to Check
- •DPF and emissions issues (diesel models)
- •Higher tyre and brake wear (larger engine)
- •Suspension wear on older models
- •Lighting defects (common on all cars)
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Find garages →BMW 3 Series vs Audi A4 FAQ
Can I compare a BMW 3 Series and Audi A4 by registration plate?
Yes. Enter each car's UK registration plate on this page or use our free compare tool at carcostcheck.co.uk/compare to see MOT history, mileage, health scores and running costs for the exact vehicles you are considering, not just model averages.
Which is more reliable, the BMW 3 Series or Audi A4?
They are level on MOT data: the BMW 3 Series and Audi A4 both have an 83% MOT pass rate (DVSA MOT data for tests in 2024, retests included).
Which is cheaper to run, the BMW 3 Series or Audi A4?
At 8,000 miles per year, the BMW 3 Series costs around £1,817 in fuel, while the Audi A4 costs around £1,817 (our estimates for petrol versions from average engine size, with fuel at GOV.UK average pump prices for the week of 5 October 2026). On these estimates they cost the same in fuel. Insurance, depreciation, and repair costs also factor into total running costs.
Should I buy a BMW 3 Series or Audi A4?
This is a very close comparison. The BMW 3 Series and Audi A4 both have an 83% MOT pass rate, so they are evenly matched on MOT results. Your decision should come down to the condition of the actual car, running costs, and which feels better to drive.
BMW 3 Series Running Costs
Full breakdown of annual costs, reliability, and MOT data
Audi A4 Running Costs
Full breakdown of annual costs, reliability, and MOT data
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