Used car guide

2018 Smart Forfour: common problems and MOT failures

What MOT testers find on the Smart Forfour first registered in 2018: we looked at the 11,318 MOTs these cars had during 2023–2025. Plus known faults and what to look at before you buy one.

11,318MOTs of 2018 cars, done in 2023–2025
81%pass first time (all 2018 cars: 83%)
4,800typical miles a year
31%had tyres flagged

Common 2018 Smart Forfour MOT failures and advisories

The share of 2018 Smart Forfour MOT tests where testers flagged each area, as a fail or an advisory. Rough prices are typical independent-garage costs.

  • Tyres
    31% of testsRough price £70–£150

    At the viewing: Check the tread on all four tyres, including the inside edges, and look for cracks or bulges.

  • Brakes
    18% of testsRough price £150–£350

    At the viewing: Look for a lip on the disc edges and feel for judder or pulling when braking firmly from about 40mph.

  • Wipers, windscreen and mirrors
    8% of testsRough price £15–£250

    At the viewing: Check for chips in the driver's view, and test the wipers and washers.

  • Lights and electrics
    7% of testsRough price £10–£80

    At the viewing: Ask a friend to check every light, including brake lights and indicators, while you operate them.

  • Suspension
    5% of testsRough price £120–£400

    At the viewing: Listen for knocks over speed bumps, and look behind each front wheel for a snapped coil spring.

  • Seats and seatbelts
    2% of testsRough price £80–£250

    At the viewing: Pull each seatbelt sharply. It should lock, and retract cleanly.

Questions to ask the seller before buying a 2018 Smart Forfour

Ask before you travel to see it. A seller who knows the car will have answers, and receipts.

  1. Can I see the service history and receipts for any big jobs?

Looking at a Smart Forfour?

Check the actual car: its own MOT history, mileage and what to ask the seller. Free, no sign-up.

Other years

Every year of the Smart Forfour compared

YearMOT testsMost flagged
2022–Too few tests
2021–Too few tests
2020–Too few tests
20195,746Tyres 28%
201714,152Tyres 32%
201615,704Tyres 33%
201516,282Tyres 32%
2007171Lights and electrics 54%
20061,378Lights and electrics 46%
20051,765Lights and electrics 48%
2004620Lights and electrics 51%

Where this comes from: the DVSA's anonymised results for every MOT test done in Great Britain during 2023–2025, counting the MOTs of Smart Forfour cars first registered in 2018. "Flagged" includes advisories, so it isn't the same as a fail rate. How we score