Open Access Transmission Tariff (OATT)

An Open Access Transmission Tariff (OATT) is a set of rules and charges established by electricity transmission owners that ensure fair and non-discriminatory access for all eligible users to the high-voltage transmission network. It facilitates the reliable transfer of electricity across different owners’ systems, allowing various energy suppliers and distributors to transmit power over shared infrastructure. By setting transparent rates and conditions, the OATT promotes competition, efficiency, and reliable delivery of electricity, helping to prevent monopolistic practices and ensuring all market participants can efficiently use the transmission grid.