Polygamy is prohibited under Sierra Leone’s Penal Code. Polygamy is authorised in customary marriages, where a man can take as many wives as he wishes.
Prevalence of polygamy
37 percent of married women in Sierra Leone were in polygamous marriages in 2008. 29.7% of married girls aged 15-19 reported that their husband had more than one wife.
References
Polygamy in Sierra Leone Wikipedia(Text) CC BY-SA