Electric vehicles (EVs) are expected to grow massively in the coming years, and grid integration of a large number of them could challenge electricity-system infrastructure. This paper aims at describing a methodology to study the technical and economic impacts on power systems of mass EV charging for several EV-owner connection behavior profiles (systematic, when necessary, when convenient) and the range of recharge modes available (uncontrolled, time-of-use tariff, smart unidirectional charging, and vehicle-to-grid). This framework is applied to a case study at hourly resolution of high penetration of electric vehicles and renewable energy sources in Europe at the 2040 time-horizon, in line with the ‘National Trends Scenario’ grid mix under the pan-EU ENTSO-E Ten-Year Network Development Plan. Results show that the European electricity system can accommodate large EV growth and that widespread adoption of smart charging in France can significantly reduce operational electricity system costs by up to 1.1 G€ and reduce carbon emissions by up to 3.2 MtCO2 per year. Multiple EV smart charging modes are also compared and the parameters have the largest impact on EV flexibility are identified, including gas prices, smart charging adoption, weekly flexibility, and mid-day charging.