Research has shown that modernization has changed people’s values. Yet, it remains unknown whether modernization has also changed ideological polarization, namely, the variability of values within the population. The paper investigates this question by analysing data from the World Value Survey about multiple countries sampled over multiple waves (339 wave-countries). Once modernization was operationalised as per capita gross domestic product, the analyses reveal that poor countries display greater ideological polarization in the domain of economics, gender equality and immigration. This fits with the idea that poor countries are predisposed to ideological polarization because they are transitioning towards modernity. Still, in domains like abortion and divorce, ideological polarization emerged to be greater in rich countries because here the population is divided between conservative and liberal positions, while most people in poor countries converge on conservative views. These observations clarify the multifaceted implications of modernization and highlight its influence upon political polarization.