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Bmw 3 Series vs Mercedes-Benz C-Class: Compare by Reg (2026)

Side-by-side comparison of the Bmw 3 Series and Mercedes-Benz C-Class, covering MOT pass rates, running costs, common faults, and overall reliability. Based on 1,582,284 real MOT tests.

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This page shows model-level MOT data. For the exact Bmw 3 Series and Mercedes-Benz C-Class you are viewing, enter a reg plate below for live MOT history, mileage checks and running costs.

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Quick Verdict

The Mercedes-Benz C-Class comes out slightly ahead with a 84% MOT pass rate versus 83% for the Bmw 3 Series. Both cars are competitive in this segment, but the Mercedes-Benz C-Class has a small edge on reliability. Consider test driving both before making your decision.

Bmw 3 Series

83%

MOT pass rate

806,092 tests

Mercedes-Benz C-Class

84%

MOT pass rate

776,192 tests

More reliable

Full Comparison: Bmw 3 Series vs Mercedes-Benz C-Class

CategoryBmw 3 SeriesMercedes-Benz C-Class
MOT Pass Rate83%84%Winner
MOT Fail Rate17%16%Winner
vs National Avg+1 pts+2 ptsWinner
Est. Fuel Cost (8,000 mi/yr)£1,076Winner£1,115
Insurance Group25-3515-25
Est. Depreciation/yr£2,000-£3,500£1,500-£3,000
Engine Size2.2L2.2L
Fuel Type(s)Diesel, PetrolHybrid, Petrol, Diesel
SegmentPremiumFamily car
Avg Mileage105,806 mi97,926 miWinner
MOT Tests Analysed806,092776,192
Model Years32 years32 years
Best Year2021 (93%)Winner2020 (92%)
Worst Year2000 (77%)Winner2004 (72%)
Reliability TrendImprovingImproving

Common Problems Comparison

Bmw 3 Series Known Issues

  • DPF and emissions issues (diesel models)
  • Higher tyre and brake wear (larger engine)
  • Suspension wear on older models
  • Lighting defects (common on all cars)
Full Bmw 3 Series common problems guide

Mercedes-Benz C-Class Known Issues

  • DPF and emissions issues (diesel models)
  • Higher tyre and brake wear (larger engine)
  • Suspension wear on older models
  • Lighting defects (common on all cars)
Full Mercedes-Benz C-Class common problems guide

Check a Specific Bmw 3 Series

Enter a reg plate to see the exact MOT history and running costs for a specific Bmw 3 Series.

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Free instant check using official DVSA and DVLA data

Check a Specific Mercedes-Benz C-Class

Enter a reg plate to see the exact MOT history and running costs for a specific Mercedes-Benz C-Class.

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Free instant check using official DVSA and DVLA data

Bmw 3 Series vs Mercedes-Benz C-Class FAQ

Which is more reliable, the Bmw 3 Series or Mercedes-Benz C-Class?

Based on MOT data, the Mercedes-Benz C-Class is more reliable with a 84% pass rate, compared to 83% for the Bmw 3 Series.

Which is cheaper to run?

At 8,000 miles per year, the Bmw 3 Series costs around £1,076 in fuel, while the Mercedes-Benz C-Class costs around £1,115. The Bmw 3 Series is cheaper on fuel. Insurance, depreciation, and repair costs also factor into total running costs.

Should I buy a Bmw 3 Series or Mercedes-Benz C-Class?

The Mercedes-Benz C-Class comes out slightly ahead with a 84% MOT pass rate versus 83% for the Bmw 3 Series. Both cars are competitive in this segment, but the Mercedes-Benz C-Class has a small edge on reliability. Consider test driving both before making your decision.

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