Personalised number plates; also known as vanity number plates, prestige number plates, cherished number plates, custom number plates or private number plates, are often highly sought after types of car registration plates. The series of letters and / or numbers which can be used, which are regulated by national authorities such as the Driving and Vehicle Licensing Agency (DVLA) in the UK, often spell out personal names, initials, places of residence, professions or other connotative combinations.

In the United Kingdom, the limitations placed on personalised number plates are: any three consecutive letters have to be followed by a number, duplicated licence plates are prohibited, i.e. when a number plate is already in use, and certain connotations such as swear words are prohibited.

Searching for permissible letter and / or number combinations can be done in a variety of ways. The DVLA has a website, offices to visit, and a personalised number plate telesales department, through all of which enquiries can be made. There are also a number of private websites which offer search functions, although it is recommended in each case to check a chosen personalised number plate with the DVLA before acquisition.

Common searches are for personal names, personal initials, symbolic dates and / or places, memorable personal dates such as birthdays or marriage dates, and titles such as Mr, Mrs, Miss, Dr, Sir and Lord. Highly popular personalised plates can often be bought and sold for significant sums at private or DVLA auctions.