Although there has been an upsurge of studies on the levels of ideological and programmatic congruence in Latin America, the analysis of the explanatory factors of congruence has been scarce.  In order to contribute to this line of research, we argue that certain characteristics of political parties, such as their age, internal coherence, level of radicalism, electoral size, and participation in government, allow them to provide clearer signals about their ideological positions to the electorate. As a consequence, we expect to find higher levels of party-voters ideological congruence among those parties that provide clearer signals about their ideology. We test this hypothesis by analyzing data from public opinion and political parties in fifteen Latin American countries between 2004 and 2010.