1.4 Million MOT Failures Linked to Number Plates as DVSA Data Reveals Biggest Causes

New DVSA data has revealed that number plates continue to catch out hundreds of thousands of motorists every year, with around 1.4 million MOT failures linked to registration plate defects and associated lighting issues.

The figures highlight just how easily drivers can fail an MOT for problems that are often inexpensive and straightforward to fix before test day.

For MOT garages, the data reinforces the importance of carrying out thorough visual inspections during servicing and pre-MOT checks, while reminding motorists that registration plates remain an essential legal and safety requirement.

Nearly Half a Million Failures for Number Plate Defects

According to DVSA figures covering Class 4 vehicles – which include most cars, taxis and light vans – there were 477,914 MOT failure items directly related to the condition or legality of number plates.

The largest reason was simply that registration plates could not be read correctly.

The data shows:

• 389,375 MOT failure items were recorded because testers were unable to read the registration plate properly
• 60,451 failures occurred because the number plate itself did not comply with legal requirements
• The remaining failures related to other defects affecting registration plate condition or security.

Unreadable number plates may result from:

• Dirt or mud obscuring characters
• Damaged or cracked plates
• Faded reflective backgrounds
• Delaminated materials
• Incorrect spacing or altered characters
• Physical damage preventing accurate identification

Under the MOT Inspection Manual, registration plates must be clearly legible from the required distance and conform to legal standards.

Number Plate Lights Cause Even More MOT Failures

While defective number plates account for hundreds of thousands of failures, the single biggest related issue is actually faulty number plate illumination.

DVSA data shows 513,316 MOT failure items were recorded because one or more number plate lights were not working.

Many motorists overlook these small bulbs because they are difficult to notice during everyday driving, yet they are mandatory equipment for vehicles fitted with rear registration plates requiring illumination.

A failed number plate light can result in an immediate MOT failure despite costing only a few pounds to replace.

Why Number Plates Matter

Registration plates are more than simply vehicle identification.

Police, DVLA enforcement teams, ANPR cameras and congestion charging systems all rely on registration plates being accurately displayed and easily readable.

For this reason, the MOT test checks that plates:

• Are securely attached
• Are clean and legible
• Display the correct font and spacing
• Use approved reflective materials
• Are not damaged or obscured
• Are correctly illuminated where required

Modified “show plates”, decorative fonts, altered spacing and tinted covers may all lead to an MOT failure if they prevent the registration mark from being read correctly.

Simple Checks Before an MOT

Many number plate-related failures can be prevented in just a few minutes.

Drivers should:

• Clean front and rear registration plates before attending the MOT.
• Check that all characters remain clearly visible.
• Replace cracked or peeling plates.
• Ensure spacing and fonts comply with legal requirements.
• Test both rear number plate lights before travelling to the test station.

These simple checks could prevent an unnecessary retest and help motorists avoid additional repair costs.

What This Means for MOT Testers

For MOT garages, the figures serve as a reminder that number plate defects remain among the most common avoidable reasons for failure.

Pre-MOT inspections provide an opportunity to identify dirty plates, damaged registrations and failed illumination before the vehicle enters the test bay, improving first-time pass rates while helping customers avoid inconvenience.

As DVSA data demonstrates, even seemingly minor defects can have a significant impact when multiplied across millions of annual MOT tests.

Key Statistics

• DVSA MOT class 3 and 4 failure statistics
• DVSA MOT open data
• Report discussing the latest DVSA number plate failure figures