v3.26.1
Cybersecurity Risk Management and Strategy Disclosure
12 Months Ended
Mar. 31, 2026
Cybersecurity Risk Management, Strategy, and Governance [Line Items]  
Cybersecurity Risk Management Processes for Assessing, Identifying, and Managing Threats [Text Block] Cyber security risk is overseen and continuously monitored by the
Group Executive and the Board. We apply the NIST cyber security
framework to identify, assess, monitor and respond to cyber security
risks, supported by a risk management process aligned to the
Group’s ERM Framework and covering all IT and operational
technology assets including systems and data, legacy technology risk
and those operated by third parties. Our cyber security risks are
managed via the “Three Lines” model, supplemented by external
specialist support including cyber security firms, providing
independent validation of our approach and specialist expertise for
specific regulatory requirements and technologies. Further assurance
is obtained through risk assessments, penetration testing, adversary
simulation, incident response exercises and compromise
assessments. An independent Supply Chain Risk Management
(SCRM) function identifies and oversees cyber risks arising from
third‑party service providers, with controls implemented by SCRM
that are proportionate to the supplier’s access to Group systems and
the sensitivity of data processed.
There have been no cyber security incidents to date that have
materially impacted the Group’s business strategy, results of
operations or financial condition. Notwithstanding this, we recognise
that the cyber threat environment for critical infrastructure providers
remains highly challenging and dynamic. We recognise that digital
transformation blurs the boundary between physical and cyber
security. Modern hybrid threats can combine common cyber attacks
with physical dimensions such as intrusion or sabotage. We have
emphasised a converged model that strengthens our ability to detect,
prevent and respond to these complex, multi-vector threats,
providing a more robust and resilient security framework.
Cybersecurity Risk Management Processes Integrated [Flag] true
Cybersecurity Risk Management Processes Integrated [Text Block] Cyber security risk is overseen and continuously monitored by the
Group Executive and the Board. We apply the NIST cyber security
framework to identify, assess, monitor and respond to cyber security
risks, supported by a risk management process aligned to the
Group’s ERM Framework and covering all IT and operational
technology assets including systems and data, legacy technology risk
and those operated by third parties
Cybersecurity Risk Management Third Party Engaged [Flag] true
Cybersecurity Risk Third Party Oversight and Identification Processes [Flag] true
Cybersecurity Risk Materially Affected or Reasonably Likely to Materially Affect Registrant [Flag] false
Cybersecurity Risk Board of Directors Oversight [Text Block] The Board is responsible for oversight of cyber security. The Audit &
Risk Committee regularly reviews reporting on our approach to cyber
security risk management and developments throughout the year.
National Grid’s Chief Information and Digital Officer (CIDO) and Chief
Information Security Officer (CISO) regularly attend the Audit & Risk
Committee and hold additional briefings to the Board at least once
per year. The Audit & Risk Committee and Board work collaboratively
to ensure oversight with the proper focus of each respective
Board committee.
Cyber risk reporting includes, among other things, current and
emerging cyber security threats to National Grid and relevant sectors,
the status of key risk indicators and controls, the results of any
relevant internal or external assessments, key incidents escalated to
management during the prior and current reporting period and the
status of cyber security improvement programmes. At the executive
and management level, the CIDO is the owner of the cyber security
risk and the CISO has primary responsibility for the development,
operation and maintenance of National Grid’s cyber security
programme. Under the CISO’s oversight, National Grid’s cyber
security team implements and provides governance and functional
oversight for cyber security services, controls and processes.
In line with our ERM Framework, cyber security processes include the
escalation of material risks and incidents, including those that
originate or occur from third parties, through the organisation to the
Group Executive Committee, Audit & Risk Committee and Board as
appropriate, based on an assessment of likelihood and severity
of impact.
Cybersecurity Risk Board Committee or Subcommittee Responsible for Oversight [Text Block] The Audit &
Risk Committee regularly reviews reporting on our approach to cyber
security risk management and developments throughout the year.
Cybersecurity Risk Process for Informing Board Committee or Subcommittee Responsible for Oversight [Text Block] The Audit &
Risk Committee regularly reviews reporting on our approach to cyber
security risk management and developments throughout the year.
National Grid’s Chief Information and Digital Officer (CIDO) and Chief
Information Security Officer (CISO) regularly attend the Audit & Risk
Committee and hold additional briefings to the Board at least once
per year. The Audit & Risk Committee and Board work collaboratively
to ensure oversight with the proper focus of each respective
Board committee.
Cybersecurity Risk Role of Management [Text Block] National Grid’s Chief Information and Digital Officer (CIDO) and Chief
Information Security Officer (CISO) regularly attend the Audit & Risk
Committee and hold additional briefings to the Board at least once
per year. The Audit & Risk Committee and Board work collaboratively
to ensure oversight with the proper focus of each respective
Board committee.
Cyber risk reporting includes, among other things, current and
emerging cyber security threats to National Grid and relevant sectors,
the status of key risk indicators and controls, the results of any
relevant internal or external assessments, key incidents escalated to
management during the prior and current reporting period and the
status of cyber security improvement programmes. At the executive
and management level, the CIDO is the owner of the cyber security
risk and the CISO has primary responsibility for the development,
operation and maintenance of National Grid’s cyber security
programme. Under the CISO’s oversight, National Grid’s cyber
security team implements and provides governance and functional
oversight for cyber security services, controls and processes.
In line with our ERM Framework, cyber security processes include the
escalation of material risks and incidents, including those that
originate or occur from third parties, through the organisation to the
Group Executive Committee, Audit & Risk Committee and Board as
appropriate, based on an assessment of likelihood and severity
of impact.
Cybersecurity Risk Management Positions or Committees Responsible [Flag] true
Cybersecurity Risk Management Positions or Committees Responsible [Text Block] National Grid’s Chief Information and Digital Officer (CIDO) and Chief
Information Security Officer (CISO) regularly attend the Audit & Risk
Committee and hold additional briefings to the Board at least once
per year. The Audit & Risk Committee and Board work collaboratively
to ensure oversight with the proper focus of each respective
Board committee.
Cybersecurity Risk Management Expertise of Management Responsible [Text Block] Chief Information and Digital Officer (CIDO) and Chief
Information Security Officer (CISO) regularly attend the Audit & Risk
Committee and hold additional briefings to the Board at least once
per year.
Cybersecurity Risk Process for Informing Management or Committees Responsible [Text Block] Cyber risk reporting includes, among other things, current and
emerging cyber security threats to National Grid and relevant sectors,
the status of key risk indicators and controls, the results of any
relevant internal or external assessments, key incidents escalated to
management during the prior and current reporting period and the
status of cyber security improvement programmes. At the executive
and management level, the CIDO is the owner of the cyber security
risk and the CISO has primary responsibility for the development,
operation and maintenance of National Grid’s cyber security
programme. Under the CISO’s oversight, National Grid’s cyber
security team implements and provides governance and functional
oversight for cyber security services, controls and processes.
In line with our ERM Framework, cyber security processes include the
escalation of material risks and incidents, including those that
originate or occur from third parties, through the organisation to the
Group Executive Committee, Audit & Risk Committee and Board as
appropriate, based on an assessment of likelihood and severity
of impact.
Cybersecurity Risk Management Positions or Committees Responsible Report to Board [Flag] true