Section 43, The Constitution of Sierra Leone, 1991

A Presidential election shall take place—a. where the office of President is to become vacant by effluxion of time and the President continues in office after the beginning of the period of four months ending with the date when his term of office would expire by effluxion of time, during the first three months of that period; b. in any other case, during the period of three months beginning with the date when the office of President becomes vacant: a. where any proceedings have been lawfully commenced or taken for the purposes of the election and assumption of office of a President, it shall not be recommended or retaken whether or not a President has thereby been duly elected, by reason only that a vacancy has occurred in the office of President otherwise than by effluxion of time; and the said proceedings shall, subject to the provision of this Constitution, be continued and committed in accordance with this Constitution and any other law for the time being in force relating thereto, with such modification as may be necessary; and b. where the office of President becomes vacant during a period when Parliament is dissolved, the Presidential election shall be held and completed before the election of Members of Parliament.