From 1994 until the present, the European Union (EU) has undergone treaty reform and enlargement, while the EP has gained new powers. The paper analyses the effect of this on the voting behaviour of Eurosceptic MEPs within the EP’s Eurosceptic groups: the European United Left/Nordic Green Left, the European Conservatives and Reformists, and European Freedom and Democracy Group, as well as all their predecessors and the MEPs who are not affiliated to any group. By analysing the total population of roll-call votes since 1994 by policy area and procedure, the paper compares the voting behaviour of the EP’s Eurosceptic parties and their internal cohesion. Eurosceptics remain divided although the more institutionalised European United Left/Nordic Green Left and the newer British-led European Conservatives and Reformist are more cohesive and alliance-oriented than the more radical Eurosceptics further to the right.