What Is a BS AU 145e Compliant Number Plate?

 you’ve recently looked at road legal number plates, you’ve probably noticed the term BS AU 145e. But what exactly does it mean, and why is it important?

BS AU 145e is the current British Standard for vehicle number plates in the UK. It sets out the legal requirements for how number plates must be manufactured, tested, marked and displayed to ensure they are durable, readable and suitable for use on public roads. Plates fitted after 1 September 2021 must comply with this standard.  

What Does BS AU 145e Mean?

BS AU 145e is the latest version of the British Standard for number plates, replacing the previous BS AU 145d standard.

The new standard became mandatory for all newly manufactured and fitted number plates from 1 September 2021 and was introduced to improve:

  • Road safety
  • Durability
  • Visibility
  • ANPR camera recognition
  • Resistance to tampering and damage

How Do I Know If a Number Plate Is BS AU 145e Compliant?

A compliant number plate must display:

  • The marking “BS AU 145e”
  • The supplier’s name and postcode
  • The manufacturer’s identification mark

These markings are usually found along the bottom edge of the plate.  

What Requirements Must a BS AU 145e Plate Meet?

A compliant number plate must:

  • Be made from approved reflective materials
  • Display black characters on a white front plate
  • Display black characters on a yellow rear plate
  • Use the correct legal font
  • Meet legal spacing requirements
  • Have no background patterns or textures
  • Be durable enough to withstand weather, dirt and road debris

Are 3D and 4D Number Plates BS AU 145e Compliant?

Yes.

3D gel and 4D number plates can still be fully road legal under BS AU 145e provided they meet all other legal requirements.

The characters must:

  • Be solid black
  • Use the correct legal font
  • Meet spacing regulations
  • Not use coloured edges, highlights or multiple shades

This means standard road legal 3D gel plates and solid black 4D plates can remain compliant.  

What Number Plates Are Not BS AU 145e Compliant?

The following examples are generally not road legal:

  • Tinted number plates
  • Smoked number plates
  • Carbon-effect backgrounds
  • Honeycomb backgrounds
  • Coloured characters
  • Two-tone 4D characters
  • Incorrect spacing
  • Illegal fonts
  • Plates without supplier details

These styles may be sold as show plates but are not suitable for road use.  

Why Was BS AU 145e Introduced?

The new standard was introduced to make number plates:

  • Easier for ANPR cameras to read
  • More resistant to weather damage
  • Less likely to fade over time
  • Harder to alter or tamper with

The aim was to improve vehicle identification and reduce the use of illegal number plates on UK roads.  

What Happens If Your Number Plates Are Not Compliant?

Using non-compliant number plates can result in:

  • MOT failures
  • Vehicle defect notices
  • Requests to replace the plates
  • Fines of up to £1,000

This is why it is important to buy number plates from a registered number plate supplier.  

Why Choose Driven Digits?

Driven Digits is a UK registered number plate supplier specialising in:

  • BS AU 145e Compliant Number Plates
  • Replacement Number Plates
  • Road Legal Number Plates
  • 3D Gel Number Plates
  • 4D Number Plates
  • 4D Retro Number Plates

Every road legal plate is manufactured to current UK regulations and requires proof of identity and entitlement before production.

Conclusion

A BS AU 145e compliant number plate is simply a number plate that meets the latest UK legal standards for durability, visibility and road use.

If you’re purchasing replacement number plates, 3D gel plates or 4D plates for use on public roads, ensuring they are BS AU 145e compliant is essential for staying legal and avoiding unnecessary issues with MOTs or law enforcement.

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