National Grid : Debt Presentation

Debt Investor Update

Half Year Results 2021/22

Alexandra Lewis, Group Treasurer

Cautionary statement

This presentation contains certain statements that are neither reported financial results nor other historical information. These statements are forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. These statements include information with respect to National Grid's (the Company) financial condition, its results of operations and businesses, strategy, plans and objectives. Words such as 'aims', 'anticipates', 'expects', 'should', 'intends', 'plans', 'believes', 'outlook', 'seeks', 'estimates', 'targets', 'may', 'will', 'continue', 'project' and similar expressions, as well as statements in the future tense, identify forward-looking statements. These forward-looking statements are not guarantees of National Grid's future performance and are subject to assumptions, risks and uncertainties that could cause actual future results to differ materially from those expressed in or implied by such forward-looking statements. Many of these assumptions, risks and uncertainties relate to factors that are beyond National Grid's ability to control, predict or estimate precisely, such as changes in laws or regulations, including any arising as a result of the United Kingdom's exit from the European Union, announcements from and decisions by governmental bodies or regulators, including the implementation of the RIIO-2 price controls; the timing of construction and delivery by third parties of new generation projects requiring connection; breaches of, or changes in, environmental, climate change and health and safety laws or regulations, including breaches or other incidents arising from the potentially harmful nature of its activities; network failure or interruption (including any that result in safety and/or environmental events), the inability to carry out critical non network operations and damage to infrastructure, due to adverse weather conditions including the impact of major storms as well as the results of climate change, due to counterparties being unable to deliver physical commodities, or due to the failure of or unauthorised access to or deliberate breaches of National Grid's IT systems and supporting technology; failure to adequately forecast and respond to disruptions in energy supply including those caused by the COVID-19 pandemic; performance against regulatory targets and standards and against National Grid's peers with the aim of delivering stakeholder expectations regarding costs and efficiency savings, as well as against targets and standards designed to deliver net zero; and customers and counterparties (including financial institutions) failing to perform their obligations to the Company. Other factors that could cause actual results to differ materially from those described in this presentation include fluctuations in exchange rates, interest rates and commodity price indices; restrictions and conditions (including filing requirements) in National Grid's borrowing and debt arrangements, funding costs and access to financing; regulatory requirements for the Company to maintain financial resources in certain parts of its business and restrictions on some subsidiaries' transactions such as paying dividends, lending or levying charges; the delayed timing of recoveries and payments in National Grid's regulated businesses, including as a result of the COVID-19 pandemic, and whether aspects of its activities are contestable; the funding requirements and performance of National Grid's pension schemes and other post-retirement benefit schemes; the failure to attract, develop and retain employees with the necessary competencies, including leadership skills, and any significant disputes arising with National Grid's employees or the breach of laws or regulations by its employees; the failure to respond to market developments, including competition for onshore transmission; the threats and opportunities presented by emerging technology; the failure by the Company to respond to, or meet its own commitments as a leader in relation to, climate change development activities relating to energy transition, including the integration of distributed energy resources; and the need to grow the Company's business to deliver its strategy, as well as incorrect or unforeseen assumptions or conclusions (including unanticipated costs and liabilities) relating to business development activity, including the integration of WPD, the sale of the Company's Rhode Island gas and electricity business and the proposed sale of a majority stake in its UK gas transmission business. For further details regarding these and other assumptions, risks and uncertainties that may impact National Grid, please read the Strategic Report section and the 'Risk factors' on pages 236 to 239 of National Grid's most recent Annual Report and Accounts, as updated by the Principal risks and uncertainties statement on page 65 of this presentation. In addition, new factors emerge from time to time and National Grid cannot assess the potential impact of any such factor on its activities or the extent to which any factor, or combination of factors, may cause actual future results to differ materially from those contained in any forward-looking statement. Except as may be required by law or regulation, the Company undertakes no obligation to update any of its forward-looking statements, which speak only as of the date of this presentation.

2 National Grid plc Half Year Results 2021/22November 2022

Key takeaways

Transactions

• WPD acquisition complete
• Rhode Island sale on track
• UK Gas Transmission sales process launched

Our businesses

• Now moved to new operating model
• >£400m pa cost efficiency programme by the end of 3 years
• Targeting
• • At least 95% of US allowed returns
  • 100bp outperformance through RIIO-T2

3 National Grid plc Half Year Results 2021/22November 2022

Financial performance highlights¹

Underlying operating profit	Underlying EPS
£1,407m 52%	22.8p	66%
HY21: £924m		HY21: 13.7p
Capital investment	Dividend growth in line with policy
£2,840m	22%	17.21p
HY21: £2,320m		HY21: 17.0p

• Excluding UK Gas Transmission which is classified as a discontinued operation, comparatives have been restated accordingly Underlying results from continuing operations, excluding exceptional items, remeasurements and timing
  Capital investment includes investment in JVs (excluding equity contributions to St William property JV) Operating profit and capital investment for continuing operations presented at constant exchange rates

4 National Grid plc Half Year Results 2021/22November 2022

Safety and reliability

• Good safety performance with lost time injury frequency rate maintained at 0.11
• Reliability was excellent
• • 95% of customers restored within 19 hours from Hurricane Elsa and Henri in the US
  • UK managed well through summer periods of low wind generation
• Winter outlook 6.6% electricity capacity margin
• UK gas network peak cold day demand well within capacity
• IFA1 return to full service expected December 2022

5 National Grid plc Half Year Results 2021/22November 2022