Do significant pro-immigration reforms--especially in the contexts where voters are anti-immigration--increase populist voting? Despite the common assumption that such reforms would lead to counter-productive voter backlash informed by the voluminous literature on immigration group threat, the extent to which immigration policy itself influences voters has been unclear. To address this question, this paper estimates the impact of immigration policy on populist voting and immigration attitudes by exploiting the timing of major changes to immigration laws in an original dataset linking the best available public opinion and policy data across the last forty years in 24 European countries. I confirm pro-immigration policies and reforms are associated with slightly higher levels of populist voting across countries. However, I also demonstrate pro-immigration (or anti-immigration) policy changes do not affect populist voting or immigration concerns within countries after accounting for time-invariant confounders. This suggests pro-immigration reforms are unlikely to backfire due to voter backlash.