This article addresses the impact of closed and flexible candidate lists on the representativeness of the lower house of the Czech Parliament from 1996 to 2021. Specifically, the paper explores representativeness according to gender, profession, residence, education, age and political experience. The effectiveness of preferential votes has manifested only since the electoral reform in 2010, mainly in the representativeness of women. Other monitored variables had a more pronounced influence, mainly in 2010 and 2013, when various citizen initiatives called for a change in the existing political set, and the new political parties disrupted the party system. Or when the voters of the PirStan coalition preferred the candidates of the STAN at the expense of the candidates of the Pirates in 2021.