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420dvs118dDiesel
  • MotorwayMotorwayRange and charging
  • PerformancePerformance0-100, top speed
  • ConsumptionConsumptionYearly cost
  • Specs420d · 118d

BMW 420d Convertible G22 vs BMW 118d F40: 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.

saloon · 2021 vs 2021 · 15,000 km/an · Mixed · Diesel 2.38 €/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 420d Convertible G22

1,643 €per year

4,6 L/100 km weighted · 10.95 € per 100 km · 692 L per year

Gap89 € per yearin favour of the 420d Convertible (−5 %)≈ 38 L diesel
BBMW 118d F40

1,732 €per year

4,9 L/100 km weighted · 11.55 € per 100 km · 729 L per year

The verdict changes with your usage
ProfileSplitAA · 420dBB · 118dGap
City70 / 25 / 570 % city · 25 % road · 5 % motorway1,725 €1,868 €143 € · 420d
Mixed30 / 50 / 2030 % city · 50 % road · 20 % motorway1,643 €1,732 €89 € · 420d
Long-distance10 / 40 / 5010 % city · 40 % road · 50 % motorway1,586 €1,632 €Nearly level

Cumulative saving for the 420d Convertible

1 year
89 €
3 years
267 €
5 years
446 €
10 years
891 €

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

What produces these figures

WLTP combined
4.5 L/100 km · 4.7 L/100 km
Powertrain
Combustion · Combustion
Power
190 ch · 150 ch
Kerb weight
1,775 kg · 1,405 kg

Other similar comparisons

AudiVSBMW

A4 40 TDI vs 420d Convertible

gap 143 €/year
BMWVSAudi

118d vs A3 Sedan

gap 24 €/year
VolvoVSBMW

S60 B4 vs 420d Convertible

gap 392 €/year
BMWVSAudi

118d vs A3 Sportback

gap 29 €/year

Frequently asked questions

On a 100 km mixed trip, the BMW 420d Convertible and BMW 118d have a near-identical cost per km with default parameters. The gap becomes significant once you enter your actual energy prices.

The BMW 420d Convertible is cheaper across all distances with default rates. If your energy prices differ significantly, simulate to see the real impact on your budget.