This research compares the degree of homophily and political polarization in Catalan MPs’ Twitter mentions network to Dutch MPs’ Twitter mentions network. Exponential random graph models were employed on a one‐year sample of mentions among Dutch MPs (N = 7,356) and on a one‐year, three‐month sample of mentions among Catalan MPs (N = 19,507). Party polar‐ ization was measured by calculating the external–internal index of both Twitter mentions networks. Results reveal that the mentions among Catalan MPs are much more homophilous than those among the Dutch MPs. Indeed, there is a positive relationship between the degree of MPs’ homophilous communication ties and the degree of political polarization observed in each network.