The third election to the Legislative Council of Ceylon was held on 21 April 1921.

Initially the Legislative Council consisted of 16 members: the British Governor, the five appointed members of the Executive Council of Ceylon, four other government officials and six appointed unofficial members (three Europeans, one Sinhalese, one Tamil and one Burgher).

In 1889 the number of appointed unofficial members was increased to eight (three Europeans, one Low Country Sinhalese, one Kandyan Sinhalese, one Tamil, one Muslim and one Burgher).

[3] Less than 3,000 Ceylonese were eligible to vote for the four elected unofficial members.

Membership was increased to 37 of which 14 were officially appointed and 23 were unofficial (11 elected on a territorial basis, five elected Europeans, two elected Burghers, one elected to represent the Chamber of Commerce, two appointed Kandyan Sinhalese, one appointed Muslim and one appointed Indian Tamil.