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120dDieselvs420iPetrol
  • MotorwayMotorwayRange and charging
  • PerformancePerformance0-100, top speed
  • ConsumptionConsumptionYearly cost
  • Specs120d · 420i

BMW 120d xDrive F20LCI vs BMW 420i F32: which is cheaper to run?

What each kilometre costs, depending on your driving profile and how you charge. Annual projection and cumulative savings over 10 years.

compact · 2018 vs 2020 · 15,000 km/an · Mixed · Diesel 2.38 €/L · Petrol 95 2.17 €/L · Methodology
Annual mileage
15,000 km
5,000 km50,000 km
Driving mix

30 % City · 50 % Road · 20 % Motorway

Fuel price
Petrol 95 2.17 €/L · Diesel 2.38 €/Lprix-carburants.gouv.fr — moyenne nationale du 05/10/2026 ; EDF Tarif Bleu Base au 01/08/2026 ; DC autoroute : moyenne des réseaux sans abonnement

Result · yearly energy cost

ABMW 120d xDrive F20LCI

1,910 €per year

5,4 L/100 km weighted · 12.74 € per 100 km · 804 L per year

Gap62 € per yearin favour of the 120d xDrive (−3 %)≈ 29 L petrol 95
BBMW 420i F32

1,973 €per year

6,1 L/100 km weighted · 13.15 € per 100 km · 909 L per year

The verdict changes with your usage
ProfileSplitAA · 120dBB · 420iGap
City70 / 25 / 570 % city · 25 % road · 5 % motorway2,046 €2,194 €148 € · 120d
Mixed30 / 50 / 2030 % city · 50 % road · 20 % motorway1,910 €1,973 €62 € · 120d
Long-distance10 / 40 / 5010 % city · 40 % road · 50 % motorway1,811 €1,803 €Nearly level

Cumulative saving for the 120d xDrive

1 year
62 €
3 years
187 €
5 years
311 €
10 years
622 €

Energy only. Excludes purchase, insurance, servicing, depreciation.

What produces these figures

WLTP combined
5.2 L/100 km · 5.8 L/100 km
Powertrain
Combustion · Combustion
Power
190 ch · 184 ch
Kerb weight
1,495 kg · 1,525 kg

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Frequently asked questions

On a 100 km mixed trip, the BMW 120d xDrive and BMW 420i have a near-identical cost per km with default parameters. The gap becomes significant once you enter your actual energy prices.

The BMW 120d xDrive is cheaper across all distances with default rates. If your energy prices differ significantly, simulate to see the real impact on your budget.