How reliable is the Mazda Demio compared with other cars?

We do not publish a comparison for the Mazda Demio, because the cars of this model that have been tested do not cover a wide enough range of ages and mileages. Its raw pass rate is 56.9% across 554 tests, but comparing a raw rate between models mostly ranks them by how new they are rather than how good they are. The failure and advisory patterns further down the page are still drawn from real tests and are worth reading.

What do testers most often warn about on a Mazda Demio?

The most common advisory is "Tyre tread depth not in accordance with the requirements", noted on 19.5% of all Mazda Demio tests. An advisory is not a failure: it flags something that will likely need attention before the next test.

What mileage does a Mazda Demio usually have at its MOT?

The average odometer reading recorded at test is 70,457 miles. This is the mileage across all tested examples of every age, not an annual figure, so treat it as a description of the fleet rather than a target for one car.

Are most Mazda Demio models petrol or diesel?

Of the Mazda Demio cars tested, 98% are petrol, 2% are diesel. Fuel type affects which items tend to fail, particularly emissions and exhaust components.

Model reliability file

Mazda Demio MOT pass rate & common failures

From 554 recorded MOT tests of the Mazda Demio, published by DVSA.

Data updated 29 July 2026

Quick answer

Across 554 MOT tests, 56.9% of Mazda Demio tests ended in a pass. This figure is not adjusted for age or mileage, so it is not a reliability ranking: the Mazda Demio fleet does not yet cover a wide enough spread of ages and distances to compare it fairly against other models. Its most commonly recorded failure is strength or continuity of the load bearing structure within 30cm of any sub-frame, spring or suspension component mounting (a 'prescribed area') is significantly reduced or inadequately repaired, which appears in 49.3% of failed tests. Cars of this model average 70,457 miles on the odometer when tested.

At a glance

Recorded pass rate

56.9%unadjusted, not comparable554 tests

We are not publishing a ranking for the Demio. The examples tested do not cover a wide enough spread of ages and mileages to compare it fairly, and an unadjusted pass rate mostly sorts models by how recently they were bought rather than how well they were built. The failure and advisory patterns below come from the same 554 tests and are worth reading on their own terms.

DVSA recorded wording

Most common failure items

Share of failed Mazda Demio tests in which each item was recorded. One failed test often lists several items, so these do not sum to 100%.

1.The strength or continuity of the load bearing structure within 30cm of any sub-frame, spring or suspension component mounting (a 'prescribed area') is significantly reduced or inadequately repaired49.3%
103 occurrencesSuspension mounting corroded or insecure explained
2.A transmission shaft constant velocity joint boot missing or no longer prevents the ingress of dirt etc22.5%
47 occurrencesDriveshaft CV joint gaiter split or missing explained
3.A lamp missing, inoperative or in the case of a multiple light source more than 1/2 not functioning13.4%
28 occurrencesLamp not working explained
4.A suspension pin, bush or joint excessively worn9.6%
20 occurrencesSuspension arm bush worn explained
5.Wiper blade missing or obviously not clearing the windscreen8.6%
18 occurrencesWiper or washer not working properly explained
6.The strength or continuity of the load bearing structure within 30cm of any seat belt anchorage (a 'prescribed area') is significantly reduced or inadequately repaired8.6%
18 occurrencesSeat belt anchorage corroded or weakened explained
7.A suspension joint dust cover missing or no longer prevents the ingress of dirt etc7.2%
15 occurrencesSuspension joint dust cover missing or split explained
8.Body, cab or chassis excessively corroded at a mounting point7.2%
15 occurrencesCorrosion in a structural area explained
9.A headlamp or light source missing, inoperative or more than ½ not functioning in the case of LED6.2%
13 occurrencesHeadlamp not working explained
10.The aim of a headlamp is not within limits laid down in the requirements5.7%
12 occurrencesHeadlamp aim incorrect explained

Warnings without a failure

Most common advisories

Share of all Mazda Demio tests carrying each advisory. The denominator differs from the failure list above because an advisory can be issued on a car that passed.

1.Tyre tread depth not in accordance with the requirements19.5%
108 testsTyre worn close to the legal limit explained
2.A tyre seriously damaged16.8%
93 testsTyre damaged or deteriorated explained
3.Brake pipe damaged or excessively corroded15.2%
84 testsBrake pipe corroded explained
4.The strength or continuity of the load bearing structure within 30cm of any sub-frame, spring or suspension component mounting (a 'prescribed area') is significantly reduced or inadequately repaired15.0%
83 testsSuspension mounting corroded or insecure explained
5.Number plate inscription missing or illegible9.6%
53 testsRegistration plate missing, insecure or illegible explained
6.A suspension pin, bush or joint excessively worn9.2%
51 testsSuspension arm bush worn explained
7.Fluid leaking excessively and likely to harm the environment or to pose a safety risk to other road users8.5%
47 tests
8.A brake hose ferrule excessively corroded8.1%
45 testsBrake hose deteriorated, damaged or chafing explained

What gets tested

The Demio fleet

Average mileage recorded at test: 70,457
Fuel mix of tested cars: Petrol98.2%
Diesel1.8%

Check a specific Mazda Demio

A model average tells you the pattern. Its own MOT record tells you the car.

Compare within the range

Other Mazda models

Mazda 2 — 69.8% adjusted
Mazda 3 — 70.6% adjusted
Mazda MX-5 — 77.2% adjusted
Mazda CX-5 — 78.5% adjusted
Mazda 6 — 73.3% adjusted
Mazda CX-3 — 83.5% unadjusted
All Mazda models

Common questions

How reliable is the Mazda Demio compared with other cars?: We do not publish a comparison for the Mazda Demio, because the cars of this model that have been tested do not cover a wide enough range of ages and mileages. Its raw pass rate is 56.9% across 554 tests, but comparing a raw rate between models mostly ranks them by how new they are rather than how good they are. The failure and advisory patterns further down the page are still drawn from real tests and are worth reading.
What is the most common MOT failure on a Mazda Demio?: The item recorded most often is "The strength or continuity of the load bearing structure within 30cm of any sub-frame, spring or suspension component mounting (a 'prescribed area') is significantly reduced or inadequately repaired", which appears in 49.3% of failed Mazda Demio tests. Because one failed test can list several items, these shares do not add up to 100%.
What do testers most often warn about on a Mazda Demio?: The most common advisory is "Tyre tread depth not in accordance with the requirements", noted on 19.5% of all Mazda Demio tests. An advisory is not a failure: it flags something that will likely need attention before the next test.
What mileage does a Mazda Demio usually have at its MOT?: The average odometer reading recorded at test is 70,457 miles. This is the mileage across all tested examples of every age, not an annual figure, so treat it as a description of the fleet rather than a target for one car.
Are most Mazda Demio models petrol or diesel?: Of the Mazda Demio cars tested, 98% are petrol, 2% are diesel. Fuel type affects which items tend to fail, particularly emissions and exhaust components.

How this was worked out

Method and limits

Figures come from the DVSA anonymised MOT testing dataset, published under the Open Government Licence. Only class 4 initial tests are counted: retests are excluded so a car appears once, and abandoned tests are excluded entirely. No adjusted rate is shown because this model's tested examples do not cover enough of the national age and mileage range for standardisation to mean anything.

An MOT measures whether a car met a legal standard on the day. It is not a breakdown record, a service history or a running-cost estimate, and a pass rate is a property of a fleet rather than a prediction about one car.