Southwest Power Pool (SPP) is a regional transmission organization (RTO) that manages the electric grid and wholesale power market for a large portion of the central and western United States. Founded in 1941 and headquartered in Little Rock, Arkansas, the nonprofit corporation oversees a service territory spanning approximately 732,086 square miles across all or part of 17 states, serving 152 members.
SPP's operations centre on energy management, grid reliability, wholesale power market operations, and transmission planning. Its Integrated Marketplace, launched in 2014, facilitates day-ahead and real-time balancing markets, transmission congestion rights, and reliability unit commitment processes. In 2025, the organisation reported delivering over $4.6 billion in value to its members, achieving a benefit-to-cost ratio of 24-to-1.
As a Federal Energy Regulatory Commission (FERC)-mandated entity, SPP is structured as a nonprofit corporation with more than 800 employees. It works within the electric utilities, energy transmission, and wholesale power market sectors, aiming to drive innovation in energy management and grid reliability across its regional footprint.
