In the UK number plates are unique. Of course you will get similar variations but you can be sure they are definitely all different. The only time you will see two identical registrations is when one has been cloned. When this happens, it can be quite a nightmare. Spare a thought then for the people in America, where even if you have a registration, there could be 68 others just like it. That's right - it is possible for one registration to be shared by 69 plates.
Marie Lai, a resident of Lisle, Illinois received traffic fines from New York even though her car was parked in her garage, 500 miles away. That's a nine hour drive! After a lot of investigating and with help from a newspaper's “Problem Solver” column, Lai found out that the offences were caused by another vehicle with the same registration.
Ernie Dannenberger, director of the vehicle services department in the Illinois secretary of state's office, said that there should not really have been any confusion. Although it is possible for commercial vehicles and domestic passenger vehicles to have same license plate numbers, commercial vehicles have a slightly smaller letter at the end of the plate character string.
So how is it possible that one registration can be on 69 vehicles? Well, these variations are possible because the state allows various custom or “specialty” plates to be issued. These variations include 18 college plates, 18 military plates and 33 other private plate versions promoting various groups and causes. The number plates are apparently distinguished from one another by a two-letter code, smaller than the main characters, which is stacked to the right of the main registration ID number.
Doesn't seem very distinguishable to me!