Transmission operational data

This page contains gas transmission data for industry analysts, including operational data for all industry stakeholders. We provide this information to reduce market uncertainty, ensure equal access to information, and increase information transparency. Our goal is to increase efficiency in the capacity and energy markets, while providing fair and timely access to operational and market information.


Gas Market Data Tools

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National Gas Transmission Data Portal

National Gas Transmission Data Portal

Our Gas Data Portal provides up-to-date and historic operational gas transmission data. View reports and data items over your chosen date range in table and graph formats - many of these are also available to export to XML or CSV format.

Go to our new data portal

Gas Data Portal 2023

Watch the webinar here 

If you would like to hear about key updates about the Gas Data Portal then please provide your information to be added to the Gas Data Portal User Community.

Join our Gas Data Portal Community

Glossary of Terms

Data API service

We offer a Pull API service for all of our customers; customers can write their own code and select the data items that they are interested in downloading. The guidance below will help you use the service to retrieve gas market information data from our website.

API for Public Webservice

API for Instantaneous Flow Webservice


MIPI Archive


Documents relating to the Market Information Provision Initiative (MIPI) system. The Gas Data Portal replaced MIPI from 24th July 2023.

Digitalisation strategy and action plan

This is an exciting time for the energy sector as we decarbonise and decentralise our energy system. Data and digitalisation are key enablers for unlocking the benefits of the energy transition and National Gas is committed to playing a leading role.

We believe in a UK future that is clean, green and thriving, where nobody gets left behind, and where digitalisation facilitates the advancement of green technologies. Through digitalisation, we can create value for consumers, improve customer experience, enable greater whole system coordination and transparency, and accelerate the development and deployment of innovative technologies.

Our Digitalisation Strategy outlines where we are today, our future strategy and our priorities. We’d love to hear your views on our approach – you can read our strategy and action plan by clicking on the links below.  Please let us know what you think by responding to our brief survey. Your feedback will help inform future versions of this strategy.

Download 2020 Digitalisation Strategy   

Download 2020 Digitalisation Action Plan

Read Ofgem's Digitalisation Strategy and Action Plan Guidance

Read Ofgem's Open Letter on Digitalisation Strategies 


2019 Digitalisation Strategy  


Supplementary reports

Bacton IP Exit NonObligated Capacity release likelihood indicator

We have committed to provide this information to the market due to the current geopolitical situation and current market conditions - this information will be continuously reviewed and updated on a weekly basis and reflects our current understanding of capability at the Bacton IP Exit point. The first forecast will be available here from 20/05/2022. From March 2023 this has not been updated and we are reviewing the need for this report. Please contact us if this is useful at [email protected]

Daily storage and LNG operator information

The information contained in this spreadsheet is published on behalf of Storage and LNG Operators under the European Regulation EC 715/2009. The data in this spreadsheet is applicable for the current gas year. Data from previous gas years can be found in the next tab.

Calculated linepack utilisation

The report below collates the hourly supply and demand flow notifications received from NTS connected sites to calculate the NTS linepack minimum value in MCM that would result from these flow profiles. Please note, connected parties update their notifications continually throughout the day; therefore, the report is accurate only at the point of publication. The report is published three times throughout the day (06:00, 12:30 and 18:30) and will reflect latest Linepack and revised supply and demand flow notifications received.

Archive - Milford Haven Weekly Capability / Capacity, Jun-Oct 2022

On 9th May Ofgem published their approval of our proposed revisions to the Entry Capacity Release Methodology Statement.

This temporary provision allows us to withhold entry capacity at Milford Haven from June to October 2022, in the Rolling Monthly Trade and Transfer System Entry Capacity (RMTnTSEC) and Weekly System Entry Capacity auctions (WSEC). The rationale for this change is driven by current geopolitical situation and current market conditions, which are expected to continue driving flows in excess of historic levels and importantly in excess of the physical capability that is achievable with summer demand levels. The ECR changes do not change the capability of the NTS in any way, but seek to protect industry and end consumers from the heightened and consistent risk of constraint costs that exists due to the current climate.

We have committed to actively forecast capability and maximise capacity release at Milford Haven on a weekly basis, and to report both capability and capacity release levels ahead of each WSEC auction. We are also committed to transparency and providing this information to you on a timely basis.

The information will be provided in a table relating to each WSEC auction period, and new data will be available for capability ~3-4 days in advance, and for capacity release ~1-3 working days in advance of the WSEC auction


We have developed a suite of pre-recorded webinars to provide guidance to the industry to aid decision-making. We are conscious that many of our operational customers work non-standard hours, so we felt that pre-recorded webinars would be beneficial as these can be viewed flexibly at times to suit operational needs.

2018 webinars

Similar to last year, this year’s Webinars will be pre-recorded to help provide more conveniently presented guidance and information. We fully appreciate that many of our operational customers work non-standard hours and therefore felt that pre-recorded webinars would be beneficial as these can be viewed at times that suit individual operational needs.

Having initially reached out to our customers, to ask which subject areas would be useful, the following webinars have been recorded. We will continue to ask the industry for subject matters to cover and record where necessary.

Operational data - detailed queries

TSO to TSO Nomination Process Contingency

Future of Gas

Emergency Response Zeus

Pre Emergency Commercial Tools

Operational Data Overview

2017 webinars

Similar to last year, this year’s Winter Webinars have been pre-recorded to help provide more conveniently presented guidance and information. We fully appreciate that many of our operational customers work non-standard hours and therefore felt that pre-recorded webinars would be beneficial as these can be viewed at times that suit individual operational needs.

Having initially reached out to our customers, to ask which subject areas would be useful, the following suite has been put together. This includes:

Gas system pressures and operational tools

  • Recap summary of what affects NTS pressure
  • What has changed recently
  • What information is available from National Grid
  • What further information is being explored to help with pressure issues
  • Daily Agreed Gas Pressures Process & Operating Margins

Emergency exercise

  • NEC background
  • Gas Deficit Emergency Stages and Actions
  • Information on Exercise Yield

Locational trades/constraint management

  • Description of what Locational Energy Actions are
  • How National Grid communicates in the event of a Locational Action being carried out
  • A working example

REMIT platform 

  • Overview of GB Remit Policy
  • Navigating round the platform, including how to post an urgent market message

SO key documents 

  • Documents covered: Winter Outlook/Review & Consultation + Gas Ten Year Statement/Future Operability Planning + Future Energy Scenarios
  • Content includes where the documents are published, how often they are published and what information they include for

MIPI – common queries 

  • To include top 10 MIPI queries, including:
  • Storage & LNG report – discrepancy in figures
  • API’s – how to register
  • CV missing data
  • Actual offtake flows – missing data

Gas Operational Forum

  • Summary of general topics covered
  • Who attends?
  • Promote the changing nature of the forums – more interactive

Pre-emergency notifications

  • Gas margins/deficit warnings
  • Safety monitors

Over the past three years, we have utilised both live webinars and standard presentations to share information with the industry which has been accessed over 1,000 times. Thank you for your interest in these and please note we are striving to improve the media of communication used and to ensure that the topics presented are of value to our customers.

Should you have any questions in relation to any of the featured webinars, please do not hesitate to contact the Operational Liaison team at [email protected] who will be able to put you in touch with the appropriate subject matter expert.

COVID-19 Webinars 2020

Gas Operations have set up a series of webinars to cover our response to the pandemic, impact on supply and demand, resilience plans, industry engagement, and a variety of other areas. Please find recordings of the webinars here-

COVID-19 Webinar 1 8th April


A wide view of National Grid workers and data display screens inside a GNCC office space

Gas query directory

To help you efficiently find the right person to talk to in relation to specific National Transmission System operational gas queries, we have developed the following contact list and directory. We have based it on the most common queries we receive from our customers. Its purpose is to make finding the right subject matter expert within National Gas, quicker and easier than ever before.

Please note that if your query relates to a home or domestic gas connection or meter exchange, please contact your network operator. You can find who your network operator is on the Energy Networks Association website.  

Download the directory