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How Check My Vehicle calculates the MOT pass rates, failure areas, mileage and recall counts shown in its used-car model guides.
Data sources
| Dataset | Details | Licence |
|---|---|---|
| DVSA MOT tests and results | DVSA anonymised MOT tests and results, 2025 extracts (dft_test_result_extracts_2025.zip, dft_test_item_extracts_2025.zip; S3 Last-Modified 19 Jun 2026; downloaded 14 Oct 2026) https://edh-dvsa-data-gov-uk-files-prod.s3.eu-west-1.amazonaws.com/ |
Open Government Licence v3.0 |
| DfT/DVLA vehicle licensing statistics (VEH0120) | DfT/DVLA df_VEH0120_UK (licensed and SORN cars by make and model), 2026 Q2 column |
Open Government Licence v3.0 |
| DVSA vehicle recalls | DVSA vehicle recalls RecallsFile.csv (S3 Last-Modified 14 Oct 2026 04:03 BST; downloaded 14 Oct 2026) https://www.check-vehicle-recalls.service.gov.uk/documents/RecallsFile.csv | Open Government Licence v3.0 |
Population
Initial (normal) MOT tests of class 4 vehicles (cars and light vans) carried out in 2025 with a result of pass, fail or pass after rectification at the station. Tests with first-use year 1971 (a DVLA placeholder date) or an invalid or future first-use year are excluded.
Definitions and formulas
- Pass rate: the share of initial MOT tests that passed first time (pass / (pass + fail + pass after rectification at the station)).
- Initial fail rate: the share of initial tests that failed or passed only after rectification at the station.
- Same-age average: for each first-use year, the model’s tests are weighted by the pass rate of all class 4 vehicles first used in that year, so a model is compared with cars of the same age.
- Difference from the same-age average: the model’s pass rate minus that average, in percentage points.
- Failure area: the share of initial tests with at least one fail or pass-after-rectification item in that top-level area (for example brakes or suspension).
- Most common failure items: the same measure for individual defects (DVSA reason-for-rejection codes), top 10 with an incidence of at least 0.5%.
- Advisories: the five most common advisory notes.
- Mileage: the median recorded mileage at each age (2025 minus the first-use year), for ages 3 to 15, excluding zero mileages and ages with fewer than 500 tests.
Suppression rules
We only show a pass-rate row for a first-use year with at least 500 tests, a mileage figure for an age with at least 500 tests, and a model guide for a model with at least 1,000 initial tests in 2025.
Known limitations
- Make and model are matched from DVSA text fields; some misspelt makes are not included.
- First-use year 1971 is a DVLA placeholder and is excluded.
- MOT results describe tested cars, not overall reliability, and say nothing about any individual vehicle.
- Recall counts are text matches at campaign level and may not affect every car.
Updates and corrections
Figures are refreshed when DVSA and DfT publish new data. To report an error, use the contact page.
Attribution
Contains public sector information licensed under the Open Government Licence v3.0. Source: DVSA anonymised MOT test data 2025; DfT/DVLA vehicle licensing statistics (VEH0120); DVSA vehicle recalls data. Not endorsed by DVSA, DVLA or DfT.
Last updated 22 October 2026 · Written by Kate