TNUoS (or The Transmission Network Use of System) charges apply to all users of Great Britain’s transmission network, recovering the cost of building, operating and maintaining the high-voltage system. Managed by the National Energy System Operator (NESO), the regime ensures all users contribute fairly to the cost of transporting electricity nationwide. Because these charges flow through to both generators and end-users, they have wide-reaching implications for the real estate sector, influencing building running costs, supply capacity decisions, and ultimately asset values.