Legislative districts of the Philippines

The legislative districts of the Philippines are the divisions of the Philippines' provinces and cities for representation in the House of Representatives. The first composition of legislative districts was enshrined in the Ordinance appended to the Constitution. Changes in the composition of legislative districts were later added as new provinces and cities were created, and the composition was modified through laws enacted by Congress.

Apportionment on local legislatures is also possible.

Representation to the legislature traces its origin to the Spanish era, when the Philippines was granted very limited representation to the Spanish Cortes. During the American period, when the Philippine Bill of 1902 was enacted, the first Philippine Assembly was established as the lower house and the then-existing Philippine Commission as the upper house. Representation in the assembly was apportioned among the provinces with respect to their population, provided that no province shall have less than one member.

In 1916, the Philippine Legislature was reconstituted with a Senate as the upper house and the Assembly retained as the lower house. The Senate elected members through Senatorial Districts, a grouping of provinces and areas of the country, while the Assembly retained its way of representation. During the Commonwealth period, the Philippine Legislature was abolished, and a unicameral National Assembly was established, with representation being like that of the Philippine Assembly, each province having at least one member depending on its population.

With the passage of the 1940 Amendments to the 1935 Constitution, a bicameral Congress was established with a House of Representatives and a Senate. The House of Representatives way of representation was like that of the Philippine Assembly, while the Senate's members were elected at large.

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