House numbering is the system of giving a unique number to each building in a street or area, with the intention of making it easier to locate a particular building. The house number is often part of a postal address. The term describes the number of any building (residential or commercial) with a mailbox, or even a vacant lot.
House numbering schemes vary by location, and in many cases even within cities. In some areas of the world, including many remote areas, houses are named but are not assigned numbers.
In many countries, the house number follows the name of the street; but in anglophone and francophone countries, the house number normally precedes the name of the street.
A house numbering scheme was present in Pont Notre-Dame in Paris in 1512. However, the purpose of the numbering was generally to determine the distribution of property ownership in the city, rather than for the purpose of organization.
In the 18th century the first street numbering schemes were applied across Europe, to aid in administrative tasks and the provision of services such as Mail delivery. The New View of London reported in 1708 that "at Prescott Street, Goodman's Fields, instead of signs, the houses are distinguished by numbers". Parts of the Paris suburbs were numbered in the 1720s; the houses in the Jewish quarter in the city of Prague in the Austrian Empire were numbered in the same decade to aid the authorities in the conscription of the Jews.
Street numbering took off in the mid-18th century, especially in Prussia, where authorities were ordered to "fix numbers on the houses ... in little villages on the day before the troops march in". In the 1750s and 60s, street numbering on a large scale was applied in Madrid, London, Paris, and Vienna, as well as many other cities across Europe. On 1 March 1768, King Louis XV of France decreed that all French houses outside of Paris affix house numbers, primarily for tracking troops quartered in civilian homes.
Due to the gradual development of house numbering and street addressing schemes, reform efforts occur periodically.