On these pages you will find out more about how the National Transmission System (NTS) handles entry and exit capacity, including how to bid for entry capacity and apply for exit capacity. You will also be able to retrieve current and historical capacity data on these pages.

Latest capacity update


Please note that the Enduring Annual Exit (flat) capacity (EAFLEC) auction has now been processed. 

For all request results (increase & decrease), please see the Enduring Annual Increase/Decrease Application Summary reports.    


Please note that the Annual NTS (flat) Exit Capacity (AFLEC) auction has been processed.

The results of the auction can be found in the Annual Sold/Unsold Quantity report.


Please note that the Long Term Exit application window will open on 1st July 2023. This window will consist of:

  • Enduring annual exit (flat) capacity increase (EAFLEC) – for enduring capacity commencing from Y+4 to Y+6
  • Enduring annual exit (flat) capacity decrease (EAFLEC) – allowing users to reduce capacity from Y+1
  • Annual NTS (flat) exit capacity (AFLEC) – for capacity covering Y+1 to Y+3

For more information, please refer to our Gas Transmission Capacity Guidelines document.


Please note that the Interim Bid Window 2 has now closed for the 2023 Quarterly System Entry Capacity (QSEC) auction.

The results of the auction can be viewed here


Please note that the Interim Bid Window 1 has now closed for the 2023 Quarterly System Entry Capacity (QSEC) auction.

The results of the auction can be viewed here


Please note that the 2023 Annual Monthly System Entry Capacity (AMSEC) auction has now officially closed. 

Results for each of the four tranches can be viewed by clicking here


Please note that the 2023 Quarterly System Entry Capacity (QSEC) auction will open on Monday 20th March 2023 at 08:00. 

For more information, please view our QSEC Presentation pack. The auction invitation can located on the Joint Office website


Please note that the 2023 Annual Monthly System Entry Capacity (AMSEC) auction will open on Monday 13th February 2023. It will consist of 4 tranches, which will take place on the following dates:

  • Monday 13th February 2023
  • Thursday 16th February 2023
  • Tuesday 21st February 2023
  • Friday 24th February 2023

Please refer to the 2023 AMSEC invitation letter for further information.  


Gemini contingency arrangements

Here you will find guidance on the Gemini Code contingency arrangements should a failure of the Gemini system occur. The processes detailed on here should only be followed when we have declared a Code contingency.

When contingency arrangements are being used, news updates will be provided via the standard communications channels:

For Gemini training materials and operational processes, please go to the Xoserve website. You can find more about Gemini contingency on the Joint Office Website.

Processes to be followed and proforma to be used in the event of a Gemini Code contingency are located here:

Download the Gemini Code Contingency Guidelines document



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To find out more about charges and how those charges are determined, please refer to the Charging pages.

Find out more