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The 1925 law of property reforms envisaged a system of total registration of interests in land (see registered land). However, it was decided that it would be too much of an administrative burden to make registration compulsory over the whole of England and Wales at the same time. Instead, England and Wales was divided into areas, and each was given a date at which registration should become compulsory. The last regions to become compulsory registration areas did so on December 1st, 1990.

The fact that registration is compulsory does not mean that everyone who owns UnregisteredLand must immediately register it. Registration is necessary when certain events take place (see events triggering first registration), such as a sale and purchase. Because land is not sold that frequently compared to other property, there does remain at the present time a small but significant area of land that is still unregistered.