SEC Version 6.4 Designated

21 January 2019

SEC v6.4 came into effect on 21st January 2019. The Secretary of State has re-designated SEC Appendix AC – Inventory, Enrolment and Withdrawal Procedures for incorporation as SEC Appendix AC – Inventory, Enrolment and Decommissioning Procedures, in order to incorporate both SMETS1-related changes and a number of consequential amendments relating to the removal of the DCC opt-out for non-domestic smart metering.

You can find a copy of the Government Response Letter here.

You can download a zip folder containing SEC v6.4 here, or download the individual sections of the SEC from the SEC and Guidance Documents page of our website. The redlined changes to these documents can be downloaded here.

If you have any questions or would like to discuss the changes to the SEC further, please contact the SEC Change Team on 020 7090 7755 or email