Mainland is usually the continental part of a region, as opposed to the islands nearby. Sometimes the residents are called "the Mainlanders". As a result of the usually larger area of mainland, there are significantly more mainlanders than islanders, and mainlander culture and politics sometimes threaten to dominate those of the islands.

Prominent uses of the term include:

• Mainland China, as opposed to the special administrative regions of Hong Kong and Macau (but including the island of Hainan), and Taiwan (and other areas administered by the Republic of China);
• Mainland Australia, as opposed to Tasmania.
• Mainland Canada, as opposed to Prince Edward Island, Newfoundland, Cape Breton Island or Vancouver Island;
• Mainland Denmark, as opposed to the Faroe Islands and Greenland (Mainland Denmark may refer to the Danish part of Jutland, as opposed to Zealand and other islands);
• Mainland Estonia, as opposed to Saaremaa, Hiiumaa and other Western Estonian islands.
• Mainland Europe, another term for Continental Europe used in many parts of the English-speaking world, but generally not in the United Kingdom; usually in Great Britain, and sometimes in Ireland, mainland Europe is referred to as The Continent.
• Mainland Finland, as opposed to Åland Islands;
• Mainland France (Le Continent), as opposed to Corsica; in relation to its Overseas Departments and Territories, the term Metropolitan France (France Métropolitaine) is more commonly used;
• Mainland United States, as opposed to the state of Hawaii and overseas territories (the terms "U.S. Mainland" and "The Mainland" are commonly used in Hawaii, but not in the U.S. mainland itself where "continental United States," which also excludes Alaska, is more commonly used instead); note: this latter term is also more precisely referred to as the "contiguous United States."
• Mainland Japan and Honshū, as opposed to the rest of the Japanese islands (see also Home Islands);
• Mainland Orkney is the largest and most populous island of the Orkney Islands in Scotland;
• the South Island of New Zealand, which, though having a far smaller population, is slightly larger than the North Island.
• the Nova Scotian mainland, as opposed to Cape Breton Island;
• British Mainland (i.e. the island of Great Britain), as opposed to the Channel Islands, the Isle of Man, Northern Ireland (although when used to differentiate Britain from Ireland it can be considered an offensive usage) or any other British island.
• Mainland Ireland as opposed to its offshore islands. Note that "the mainland" in Northern Ireland is ambiguous between this sense and the preceding one; using the phrase to mean "Great Britain as opposed to Northern Ireland" is considered objectionable by many Nationalists.
• The largest islands of the Orkney and Shetland Islands; see Mainland, Orkney and Mainland, Shetland.
• Mainland Portugal as opposed to Azores and Madeira Islands.
• Mainland Korea as opposed to Jeju and Ulleung Islands
• Mainland Spain as opposed to the Balearic and Canary Islands, the North African cities of Ceuta and Melilla, the island of Alborán and other minor exclaves on Northern Africa (called the Plazas de soberanía). In Spain the terms "España peninsular" or simply "La Península" are often used.