What does 0.1 mean on an MOT certificate?

It refers to sub-section 0.1 of the MOT inspection manual, "Registration plates", within section 0, identification of the vehicle. The letter or letters after it — (a), (b)(i) and so on — identify the specific defect from the 4 listed here. 4 Major and 0 Minor.

Which registration plates defect is recorded most often?

"Number plate does not conform to the specified requirements" (0.1 (d)), recorded about 0.3 times per 100 failed MOT tests nationally. We explain what it means and what puts it right.

Does a Minor defect fail the MOT?

No. a defect with no significant effect on safety or the environment. Recorded on the certificate; the vehicle passes. Major and Dangerous defects fail. A Dangerous defect also means the car must not be driven until it is repaired.

Section 0 · Identification of the vehicle

0.1 Registration plates

Manual indexed 3 September 2026

Quick answer

Sub-section 0.1 of the MOT inspection manual covers registration plates and lists 4 defects. A reference like "(0.1 (a))" on a certificate points to the matching row below. The most recorded is "Number plate does not conform to the specified requirements", about 0.3 times per 100 failed tests.

Official wording

The defect clauses

0.1 (a)Majorunder 0.1 per 100 fails
Number plate missing or so insecure that it is likely to fall off
Registration plate missing, insecure or illegible explained: what it means and what puts it right
0.1 (b)Majorunder 0.1 per 100 fails
Number plate inscription missing or illegible
Registration plate missing, insecure or illegible explained: what it means and what puts it right
0.1 (c)Majorunder 0.1 per 100 fails
Number plate showing an incorrect registration
Registration plate missing, insecure or illegible explained: what it means and what puts it right
0.1 (d)Major0.3 per 100 fails
Number plate does not conform to the specified requirements
Registration plate missing, insecure or illegible explained: what it means and what puts it right

Wording and categories reproduced from the DVSA inspection manual under the Open Government Licence. Frequencies are items per 100 failed class 4 tests across the DVSA anonymised MOT dataset; a clause with no figure was not recorded often enough to appear in any model’s top forty failure items. 4 of 4 clauses link to our own explanation.

Grading

What the categories mean

Dangerous: a direct and immediate risk to road safety or the environment. The vehicle fails and must not be driven until repaired, even to a garage.
Major: a defect that affects safety, the environment or other road users. The vehicle fails.
Minor: a defect with no significant effect on safety or the environment. Recorded on the certificate; the vehicle passes.

The full guide to defect grading

Section 0

Other sub-sections of identification of the vehicle

0.2Vehicle identification number (VIN)

All sections of the manual

Common questions

What does 0.1 mean on an MOT certificate?: It refers to sub-section 0.1 of the MOT inspection manual, "Registration plates", within section 0, identification of the vehicle. The letter or letters after it — (a), (b)(i) and so on — identify the specific defect from the 4 listed here. 4 Major and 0 Minor.
Which registration plates defect is recorded most often?: "Number plate does not conform to the specified requirements" (0.1 (d)), recorded about 0.3 times per 100 failed MOT tests nationally. We explain what it means and what puts it right.
Does a Minor defect fail the MOT?: No. a defect with no significant effect on safety or the environment. Recorded on the certificate; the vehicle passes. Major and Dangerous defects fail. A Dangerous defect also means the car must not be driven until it is repaired.