The introduction of flow-based market coupling (FBMC) within the Core region represented a major step forward in European power market integration. Under the flow-based market coupling mechanism, transmission system operators manage transmission capacity using Critical Network Elements with Contingencies (CNECs) – specific transmission lines and their associated outage scenarios. These CNECs define the physical constraints that determine the range of feasible power exchanges within the Core region. Instead of relying on fixed transfer capacities, FBMC dynamically adjusts market coupling results to ensure that network flows remain within these operational limits. In theory, this mechanism should enhance price convergence and promote efficient cross-border electricity trading. In practice, however, throughout 2024 and 2025, the High-Price Region – comprising Hungary, Romania, Serbia, Bulgaria, Greece, and Croatia – has faced persistently higher prices than its Central European neighbours.