2021 Kia Niro 4 Ev — MOT failures & pass rate

Across 17,513 MOT tests analysed for the 2021 Kia Niro 4 Ev, the most common recorded failure areas were tyres, visibility and lighting & signalling. Its pass rate of 92.4% was in line with the average for cars of a similar age (91.4%).

92%
Pass rate
17,513
MOT tests analysed
7.6%
Fail rate
in line with
vs cars of similar age
3.4
Avg age at test (yrs)

How it compares

Fail rate vs benchmarks (lower is better) 2021 Niro 4 Ev 7.6% cars avg 8.6% National avg 8.5%
Fail rate for this model-year against the segment and national averages for cars of a similar age.

Top failure categories

Most common MOT failure areas — 2021 Kia Niro 4 Ev
# Category % of tests affected Tests
1 Tyres 5.9% 1,041
2 Visibility 2.7% 468
3 Lighting & signalling 1.5% 267
4 Brakes 0.4% 73
5 Suspension 0.2% 28
6 Other defects 0.1% 21
Share of tests failing on each category Tyres 5.9% Visibility 2.7% Lighting & signalling 1.5% Brakes 0.4% Suspension 0.2% Other defects 0.1%
Percentage of tests with at least one failure recorded in each category.

Most common specific failures

The exact components most often recorded as failures — more specific than the categories above.

Most frequently recorded failure items — 2021 Kia Niro 4 Ev
#Failure itemTimes recorded
1Wipers490
2Tread depth485
3Headlamp aim154
4Registration plate lamp(s)79
5Washers64
6Service brake performance41

Top advisory categories

Advisories aren't failures, but they flag work likely needed soon — useful when budgeting.

Most common MOT advisories — 2021 Kia Niro 4 Ev
# Category % of tests with advisory Tests
1 Tyres 21.6% 3,787
2 Other defects 5.5% 958
3 Brakes 4.1% 717
4 Visibility 2.7% 470
5 Lighting & signalling 0.8% 140
6 Suspension 0.8% 138

Failure rate by mileage

Higher-mileage cars tend to fail more — often the most useful guide to real condition.

MOT fail rate by recorded mileage 0-30k 6.4% 30-60k 8.9% 60-90k 7.1% 90-120k 7.0% 120-150k 4.3% 150k+ 7.5%
MOT fail rate by recorded mileage band.
Fail rate by recorded mileage — 2021 Niro 4 Ev
Mileage band Tests Fail rate
0-30k 6,574 6.4%
30-60k 7,877 8.9%
60-90k 2,071 7.1%
90-120k 633 7.0%
120-150k 211 4.3%
150k+ 147 7.5%

Failure rate by age

MOT fail rate by vehicle age at test 1 yr 2.7% 2 yrs 4.5% 3 yrs 7.7% 4 yrs 8.2%
How this model-year's MOT fail rate climbs as the cars get older.

Trend over time

Fail rate by dataset year — 2021 Niro 4 Ev
Dataset year Tests Fail rate
2022 448 2.7%
2023 1,037 4.5%
2024 7,910 7.7%
2025 8,106 8.2%

What to check before buying a 2021 Niro 4 Ev

Before buying a 2021 Kia Niro 4 Ev, focus on the areas it most often fails on. Tyres accounted for 5.9% of tests for this year.

Repair costs are rough UK ballpark ranges to set expectations, not quotes — actual prices vary widely by car, parts and garage.

Frequently asked questions

How many 2021 Kia Niro 4 Evs pass their MOT?

92.4% of the 17,513 2021 Kia Niro 4 Ev MOT tests in this dataset passed — a 7.6% fail rate.

What is the most common MOT failure on a 2021 Kia Niro 4 Ev?

Tyres, recorded in 5.9% of tests, followed by visibility (2.7%).

Does the 2021 Niro 4 Ev get worse with mileage?

Its MOT fail rate rises from 6.4% in the 0-30k band to 7.5% in the 150k+ band.

Methodology & source. Based on 17,513 MOT tests. Dataset: DVSA MOT testing data (2021,2022,2023,2024,2025). Data last updated 2026-07-01. Figures reflect MOT-testable defects only — read the methodology for how these are calculated and what they don't measure.

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