Vehicle-to-grid (V2G) could help balance and regulate the electricity grid. While research papers have focused primarily on the technological potential of V2G services and consumer adaptation, the institutional barriers obstructing the industry from implementing V2G are hardly researched. This study, therefore, explored these institutional barriers using grounded theory and stakeholder interviews. The results showed an array of barriers related to communication standard ambiguity, non-harmonised and undefined network codes, charging standard ambiguity resulting in uncertainties and financial risks, and conflicting stakeholder needs about who should control V2G operations. We conclude that large-scale adoption of V2G in Europe is hindered because it is unclear to the actors involved how to become ”V2G-ready”. This lack of clarity results in an innovation that is in a wait-and-see phase. We give practical recommendations to potentially become V2G-ready and for further research.