Vehicle registration plates came into existence in the United Kingdom in 1904. The majority of vehicles are required by law to display a valid plate. The legislation that first required the carrying of number plates was the Motor Car Act 1903, which came into force at the start of 1904. This statute required all vehicles to be registered and as such, each vehicle was assigned a specific identifying number. This law came into being in order for vehicles to be traceable should they be involved in an accident or criminal activity.

UK registration plates are square or rectangular in shape and the law dictates the exact dimensions of the lettering contained within them. This includes the spacing between the characters as well as the width and height of the characters themselves. From 1st September 2001, it became mandatory for licence plates to be printed using one specific typeface. All plates must be in accordance with the Road Vehicles (Display of Registration Marks) Regulations 2001. For all vehicles manufactured from 1973 onwards this means that the plates must be made from reflex-reflecting material. Front plates should be white while rear plates are yellow and both contain black characters only. Only vehicles manufactured prior to 1973 are permitted to carry black plates with silver, grey or white letters and numbers.

The standard size for front number plates is 520mm x 111mm. Most rear plates are the same size, but they can also measure 285mm x 203mm or 533mm x 152mm.