Used car guide · 2016–2022

Toyota Prius Mk4: best and worst years, and what goes wrong

How each year of the Toyota Prius Mk4 did at the MOTs done during 2023–2025, compared with other cars the same age, the weak spots that keep coming up, and what to check before you buy one. From 215,401 MOT tests.

2017best year: 87% pass first time, 7 points above all 2017 cars
2020weakest year: 87% pass first time, 0 points above all 2020 cars
Number plate lightsthe weak spot that shows up in 2 different years

Which Toyota Prius Mk4 years are best and worst at their MOT?

First-time MOT pass rate for each year of the Toyota Prius Mk4, against all cars registered the same year. Older cars fail more, so the comparison with cars the same age is what matters.

60%80%100%2016: 84% pass first time (all 2016 cars: 77%) 84% 2016*2017: 87% pass first time (all 2017 cars: 80%) 87% 20172018: 88% pass first time (all 2018 cars: 83%) 88% 20182019: 87% pass first time (all 2019 cars: 85%) 87% 20192020: 87% pass first time (all 2020 cars: 87%) 87% 20202021: 91% pass first time (all 2021 cars: 87%) 91% 20212022: 92% pass first time (all 2022 cars: 89%) 92% 2022
This model, first-time pass rate All cars registered that year · * changeover year: some cars are the previous or next generation
YearPass first timeAll cars that yearStands outMOT tests
2016*84%77% +7Link ball joint covers 4.6× usual43,989
201787%80% +7Link ball joint covers 6.7× usual45,148
201888%83% +5Nothing unusual42,725
201987%85% +2Number plate lights 3× usual47,795
202087%87% +0Number plate lights 4.9× usual26,304
202191%87% +4Nothing unusual6,606
202292%89% +3Nothing unusual2,834

Common Toyota Prius Mk4 MOT failures, year after year

Parts flagged at MOT well above the usual rate for cars the same age, in more than one year of this generation. Repeat findings like these are much less likely to be chance.

  • Number plate lightsup to 4.9× usual

    Stands out in 2 years: 2020, 2019.

    Rough price £5–£40 our estimate

    At the viewing: Check the number plate lights work and the plates are clean and legal.

What usually goes wrong with the Toyota Prius Mk4?

From owners, mechanics and UK buying guides, in our own words. Not every car will have them.

  • Fire-risk and parking brake recalls

    About 32,000 UK cars were recalled in 2018 for a possible fire risk, and others for the parking brake (2016), passenger airbags and an ECU check (2020).

    Check: Ask a Toyota dealer to check the VIN for outstanding recalls.

    Source: Auto Express: used Toyota Prius (Mk4, 2015-2022) review

Where this comes from: the DVSA's anonymised results for every MOT test done in Great Britain during 2023–2025, counting each car's main test of the year (not retests). A weak spot needs at least 30 cars flagged and must stay 1.5× the usual rate even at the cautious end of a 95% confidence range. Generation years are approximate: cars registered in a changeover year (*) can be either generation. How we score

Looking at a Toyota Prius?

Check the actual car: its own MOT history, whether it already shows these weak spots, and what to ask the seller. Free, no sign-up.