Choosing a candidate to vote for is particularly demanding for voters in open-list electoral systems. To cope with the high cognitive load, voters often resort to cognitive short cuts, i.e. heuristics. Most of these heuristics - personal vote earning attributes - are related to candidates’ political experience and local roots, i.e., factors that make them recognizable for the wider electorate. However, research also shows that more cognitively demanding information, namely candidates’ ideological positions, influence their intraparty electoral success. Yet, little is known about the contexts in which candidates’ ideological positions become an important factor for voters. In this paper, we test whether electoral complexity, operationalized via candidate recognizability index, conditions the effect of candidates’ ideological positioning using data from three Finnish parliamentary elections and two voting advice applications. Presence of recognizable candidates in a party list was seen as a manifestation of low complexity, whereas a list without candidates having any recognizable traits was interpreted as electorally complex. The results revealed that ideological positions mattered most when electoral complexity was high, which is contrary to the expectations of the previous research. We theorize that when facing a list of unknown candidates, voters are more prone to rely on ideological cues.