What is Queue Management?

To support the connection of projects to the electricity network to achieve targets for Net Zero, on 13 November 2023, Ofgem approved the Connection and Use of System Code (CUSC) Modification ‘CMP376: Inclusion of Queue Management process within the CUSC’

This means from 27 November 2023, Transmission Connection Offers will have queue milestones added to their contracts to ensure projects are actively progressing towards their connection to the network. This addition will provide National Grid Electricity System Operator (NGESO) the ability to terminate projects which are not progressing against the milestones and remove them from the connections queue.

If the Customer still requires a Transmission connection following termination, they must reapply for their connection capacity.

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How will Queue Management impact our customers?

Queue Management will apply to all new applications, any new modification applications and new agreements to vary for parties with a CUSC Construction Agreement.*

*except BEGAs, DNOs associated with Distributed Generation (DG) or demand customer connections; and shared works for non-radical offshore connections and any Offshore Transmission System User Development Works (OTSDUW).

Customers with a contracted Completion Date of 2 years or more, or projects not progressing with a Completion Date of less than 2 years, will receive a letter from the ESO, outlining two options: 

Option 1:

Customer may submit a Modification Application for a new Completion Date

➢ Queue Management milestones will be added to their agreement, aligned to the new allocated Completion Date in a forward-looking manner.

➢ A revised Completion Date will be provided by the TO to the NGESO who will update the agreement with the Customer.

➢ A standard Modification Application fee would be charged for this option.

Option 2:

NGESO will issue an Agreement To Vary (ATV) to modify Construction Agreement and add Queue Management milestones aligned to their existing Completion Date.

➢ Milestones will be added in a forward-looking manner.

Customers will need to decide which option to follow within 6 months of the Queue Management Implementation Date and TOs and NGESO will ensure these changes are managed efficiently. Where the customer does not submit a Modification Application within 6 months of the Implementation Date or does not accept the Modification Offer made in response to this, NGESO will issue an ATV as soon as practicable after the 6 months or failure to accept.

Useful Information

  • Ofgem Decision

    Ofgem are the energy regulator for Great Britain and have announced the changes to the customer connection process, if you would like more information please read their Queue Management decision announcement.

  • NGESO Overview of Queue Management

    Please read the NGESO Queue Management information page to find out more about the decision.

  • NGESO QM Customer Guide

    NGESO, is the electricity system operator for Great Britain and you can read their Customer Guide for more information on the Queue Management process.

    The guide will be available from 27 November.


Milestones will be added to the Customer’s construction agreement and will be dated, counting back from the contracted Completion Date provided by NGESO.

Milestones will be applied to track the Customer’s progress towards completion.

If you’re a customer in the connections queue, you can use the NGESO milestone calculator to identify key dates your project needs to meet to keep your place in the connections queue.

Further information on Milestones can be found on the NGESO website.


It has been agreed that there may be exceptional circumstances that are beyond Customers control which may lead to projects delays. If a Customer believes this applies to them, they must contact NGESO and provide evidence than an exception applies.

The exceptions include:

  • Where the Customer is delayed in carrying out the Customer’s Works which entitles the Customer to fix a later date or dates under Clause 3.2 of the Construction Agreement (Delays and Force Majeure) and that delay is the reason that a Customer Progression Milestone is not met.

  • Where the Customer is not able to meet a Customer Progression Milestone due to an event of Force Majeure.

  • Where delays caused by a party (other than the Customer, The Company or a Relevant Transmission Licensee) can be demonstrated to have an impact upon the Customer meeting a Customer Progression Milestone and the Customer could not have avoided these delays or their impact by the exercise of Good Industry Practice.

  • Where a Customer is not able to meet a Customer Progression Milestone due to Planning appeals and third-party challenges in relation to the Customer’s Consents; and

  • Any delay in the achievement of a milestone by the Customer which is caused by a Relevant Transmission Licensee or The Company.

Modification Applications

If a Customer has a Construction Agreement that was issued before Queue Management was implemented, and they wish to submit a modification application to make any changes to their current Offer, then Queue Management milestones will be added to their contract.


Customer's must provide evidence that they have met their Queue Management milestones to NGESO prior to reaching their milestone date.

For Milestones 1 – 3, failure to provide the requested documentation will result in the NGESO terminating the Customer’s Construction Agreement.

For Milestones 5 – 8, NGESO have the right to terminate the Customer’s construction agreement. This will be determined by an internal NGESO escalation process. More information of which can be found in NGESO’s Queue Management Customer Guide.

If a Customer fails to provide adequate evidence that they have met the milestone, this means they will be removed from the connections queue and will have to reapply. Terminated Customers will not be relocated within the queue, they will be removed.


For any queries relating to appeals and disputes, please consult section 7 of the CUSC.

For disputes on specified items within the Construction Agreement, please consult Clause 6 of the Construction agreement.

Appeals/Disputes should be treated as a last resort and any grounds for appeal must be clearly linked to the Milestone evidence.

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Contact Information

If you have any questions on what this means for you, or you would like any extra information, please contact your Contract Manager at NGESO or visit their website.
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