Grid Code Modifications

You can raise a modification – or mod – when you want to propose a change to any part of the Grid Code

For more information, please contact [email protected]

Search for any current or concluded modifications by name or ID. You can sort mods by ID, name, status or date of update. Or filter according to status.

Modification Requests

Modification status
ID Name Status Last Updated Sort ascending Link to modification
GC0181 GC0181: Enhance the Effectiveness of System Incidents Reporting Current view
GC0187 GC0187: Grid Code Legal Text Corrections 2026 Current view
GC0169 GC0169: Material changes arising from Grid Code Modification GC0136 Current view
GC0173 GC0​173​: Consistency of Technical and Compliance Requirements between GB and European Users Current view
GC0103 GC0103: The introduction of harmonised Applicable Electrical Standards in GB to ensure compliance with the EU Connection Codes Current view
GC0188 GC0188: Update for Centralised Strategic Network Plan Current view
GC0164 GC0164: Simplification of Operating Code No.2 Current view
GC0168 GC0168: Submission of Electro Magnetic Transient (EMT) Models Current view
GC0182 GC0182: Standardisation of Power Flow Metering Polarity Current view
GC0139 GC0139: Enhanced Planning-Data Exchange to Facilitate Whole System Planning Current view

More about modifications

Modification Tracker

Our Tracker gives you the latest details on current code modifications including the purpose and the stakeholders it affects, as well as panel comments and where it is in the review process. It is published on the 7th (or next working day) of each month.

Raise a modification

If you're thinking about raising a modification, please get in touch with us. Our experts can give you advice on your Proposal, explain how the modification process works and help to answer any questions you may have. When we receive your Proposal, we'll check it through and work together to make sure it's easy to understand.

Calendar

Once you've been in touch and are ready to write your Proposal paper, send it to us by the monthly modification submission date which you can find on our Calendar.