As of March 31, 2026, the Smart Electric Power Alliance (SEPA) Database of Emerging Large Load Tariffs indicated that state policymakers are looking to large load tariffs as a way to shield ratepayers from the surge in interconnection requests from data centers, with 77 tariffs pending or in place across 36 states. [1] In 2025, state regulators approved 29 large load tariffs, compared to 14 between 2018 and 2024. [2] The database has added 12 entries and 3 more states since it was last updated in November 2025. The definition of large load has evolved as the size of projects have grown; utilities used to define them using a threshold of five, 10, or 25 MW a few years ago, but now define them as 50 MW or more. These tariffs ask loads to pay more of the upfront costs for studies or power delivery infrastructure, minimum contract terms, minimum load guarantees, and more, in case a project falls through. Early evidence shows that although it is too soon to tell if tariffs are effective, they can eliminate speculative requests from the pipeline. AEP Ohio cut its large load forecast by over 50% after a large load tariff was approved in 2025 despite inflated data center demand.

[1] https://sepapower.org/large-load-tariffs-database/

[2] https://dis.puc.state.oh.us/CaseRecord.aspx?CaseNo=24-0508