MOSL manages changes to the Market Arrangements Code (MAC) and Wholesale Retail Code (WRC) on behalf of the non-household market. Changes can be proposed by any industry participant and MOSL supports proposers to design and develop proposals prior to Panel review and Ofwat determination whether to implement the proposal. This page provides information on current changes, how to engage with the change process and how to propose new changes.

MOSL prepares a change report for the Panel each month describing the progress of each change proposal and the anticipated implementation programme.  The current change report can be downloaded from the link on the right.  Previous reports can be downloaded in the Panel papers.

MOSL may consult on behalf of the Panel to gather evidence on the need for and impact of a change proposal. Input from market participants and customers is welcomed and live consultations can be accessed through the link on the right.

If you wish to raise a change please follow the link on the right which provides templates and contact details to submit changes.

The Change Register below shows all proposals that have been formally submitted to change the Market Arrangements Code (prefixed CPM) or Wholesale Retail Code (prefixed CPW). Please use the filter and sort functions to navigate past and current changes and click on a change to view the documents associated with it.

Change Register

Reference Title Status Implementation date
CPW014 CSD 0301 Updates Implemented 18/05/2018
CPW015 CSD 0101 Clarification Implemented 02/10/2017
CPW016 CSD0104 Clarification – Meter Networks Implemented 02/10/2017
CPW017 CSD0105 Clarifications and updates Implemented 02/10/2017
CPW018 Clarification of Unsecured Credit Allowance Implemented 23/04/2018
CPW019 Alternative Eligible Credit Support Implemented 31/07/2018
CPW020 Proposal to amend the wording in the F02 Complaint Form Implemented 01/12/2017
CPW021 Negotiating Alternative Eligible Credit Support reasonably and in good faith Implemented 14/07/2017
CPW022 New Connection Retailer Unknown Implemented 18/05/2018
CPW023 Market Entry and Re-Assurance Updates Implemented 12/03/2018
CPW024 Settlement Renaming and Report Issuing Updates Implemented 01/12/2017
CPW025 Extending TCORR Functionality for Inactive Data Items Implemented 17/05/2019
CPW026 Removing SPID version design Implemented 28/09/2018
CPW027 QC Error Code Implemented 18/05/2018
CPW028 Unpaired SPIDs Implemented 28/09/2018

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