Sierra Leone does not allow dual or multiple at the same time for its citizens, according to its citizenship legislation.
Dual citizenship
No person shall have Sierra Leone citizenship and any other citizenship at one and the same time.
Loss of Sierra Leone citizenship by person of dual citizenship
Any person who, upon attaining the age of twenty-one years, is a citizen of Sierra Leone and also a citizen of another country shall cease to be a citizen of Sierra Leone upon his attaining the age of twenty-two years, (or in the case of a person of unsound mind, at such later date as may be prescribed) unless he has complied with paragraphs (a), (b) and (c) of section 9.
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