Radical right parties, a party family that experienced immense electoral success over the past decades, are widely viewed as dominant actors in the politicization of immigration. As anti-immigration ideologies are a common feature of the radical right, their crucial role in making immigration a high-salience issue is hardly questioned. Recent findings from a longitudinal, comparative media analysis of claims conducted as part of the FP7-project Support and Opposition to Migration (SOM; http://www.som-project.eu/) challenge this widespread assumption. In the six countries under investigation, mainstream left and center-right parties are stronger claimants then radical right parties, the overall issue-salience cannot be related to the strength of radical right parties and there is no evidence of an influence of radical right parties’ issue-emphasis to be reflected in the overall salience of immigration. On the other hand the contents of claims made by radical right parties are predominantly negative in all countries under investigation, a fact that highlights the radical right parties’ role in polarization. The article provides empirical evidence and reflections on these new findings and embeds them in the broader discussion on radical right parties and immigration. Strengths and limitations of political claims analysis as a method for research on the radical rights’ role in issue-politicization of immigration are discussed. Finally, we suggest a more precise assessment of the larger process of issue-politicization in which radical right parties are mainly involved through the polarization of immigration.