This paper combines gravity theory and cleavage theory to explain voter volatility in 20 European countries from 2002 to 2024. For the first time, we show that (Newtonian) gravity theory, derived from trade models, is a useful tool for predicting both the extent of vote switching across party dyads over time and vote choice stability. We implement cleavage theory by examining the distinctiveness of a party’s social structure as a constraint on voter volatility. Using Dutch and Swiss Household panel data alongside European Social Survey Data, we find that an integrated gravity-cleavage model powerfully predicts stability and volatility in voting preferences across states with diverse institutional and social structures.