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The Connection and Use of System Code

The Connection and Use of System Code (CUSC) constitutes the contractual framework for connection to, and use of, National Grid’s high voltage transmission system.

The CUSC Framework Agreement which gives contractual effect to the licence based CUSC shows all persons who were party to the MCUSA as at the CUSC Implementation Date and are Original Parties to the CUSC Framework Agreement.

The list of current users, updated from time to time, is contained in Schedule 1 of the Schedules and Exhibits below.

This link will take you to our Code Summaries page which includes a summary of the CUSC.

If you wish to apply to connect to or use the National Grid Transmission System or interconnector, then please click on the application forms.