Nationwide Building Society : SUPPLEMENT DATED 14 DECEMBER 2022 TO THE COVERED BOND BASE PROSPECTUS

IMPORTANT NOTICE

IMPORTANT: You must read the following before continuing. The following applies to the supplement (the Supplement) following this page, and you are therefore advised to read this carefully before reading, accessing or making any other use of the Supplement. In accessing the Supplement, you agree to be bound by the following terms and conditions, including any modifications to them any time you receive any information from us as a result of such access.

NOTHING IN THIS ELECTRONIC TRANSMISSION CONSTITUTES AN OFFER OF SECURITIES FOR SALE IN ANY JURISDICTION WHERE IT IS UNLAWFUL TO DO SO. THE SECURITIES HAVE NOT BEEN, AND WILL NOT BE, REGISTERED UNDER THE US SECURITIES ACT OF 1933, AS AMENDED (THE SECURITIES ACT), OR THE SECURITIES LAWS OF ANY STATE OF THE US OR OTHER JURISDICTION AND THE SECURITIES MAY NOT BE OFFERED, SOLD OR DELIVERED WITHIN THE US OR TO, OR FOR THE ACCOUNT OR BENEFIT OF, US PERSONS (AS DEFINED IN REGULATION S UNDER THE SECURITIES ACT), EXCEPT PURSUANT TO AN EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT AND APPLICABLE LAWS OF OTHER JURISDICTIONS.

THE FOLLOWING SUPPLEMENT MAY NOT BE FORWARDED OR DISTRIBUTED TO ANY OTHER PERSON AND MAY NOT BE REPRODUCED IN ANY MANNER WHATSOEVER. ANY FORWARDING, DISTRIBUTION OR REPRODUCTION OF THIS DOCUMENT IN WHOLE OR IN PART IS UNAUTHORISED. FAILURE TO COMPLY WITH THIS DIRECTIVE MAY RESULT IN A VIOLATION OF THE SECURITIES ACT OR THE APPLICABLE LAWS OF OTHER JURISDICTIONS.

THE COVERED BONDS ARE NOT INTENDED TO BE OFFERED, SOLD OR OTHERWISE MADE AVAILABLE TO AND SHOULD NOT BE OFFERED, SOLD OR OTHERWISE MADE AVAILABLE TO ANY RETAIL INVESTOR IN THE EUROPEAN ECONOMIC AREA (THE EEA). FOR THESE PURPOSES, A RETAIL INVESTOR MEANS A PERSON WHO IS ONE (OR MORE) OF: (I) A RETAIL CLIENT AS DEFINED IN POINT (11) OF ARTICLE 4(1) OF DIRECTIVE 2014/65/EU (AS AMENDED, MIFID II); OR

1. A CUSTOMER WITHIN THE MEANING OF DIRECTIVE (EU) 2016/97, AS AMENDED OR SUPERSEDED (THE INSURANCE DISTRIBUTION DIRECTIVE), WHERE THAT CUSTOMER WOULD NOT QUALIFY AS A PROFESSIONAL CLIENT AS DEFINED IN POINT (10) OF ARTICLE 4(1) OF MIFID II. CONSEQUENTLY, NO KEY INFORMATION DOCUMENT REQUIRED BY REGULATION (EU) NO. 1286/2014 (AS AMENDED, THE PRIIPS REGULATION) FOR OFFERING OR SELLING THE COVERED BONDS OR OTHERWISE MAKING THEM AVAILABLE TO RETAIL INVESTORS IN THE EEA HAS BEEN PREPARED AND THEREFORE OFFERING OR SELLING THE COVERED BONDS OR OTHERWISE MAKING THEM AVAILABLE TO ANY RETAIL INVESTOR IN THE EEA MAY BE UNLAWFUL UNDER THE PRIIPS REGULATION.

THE COVERED BONDS ARE NOT INTENDED TO BE OFFERED, SOLD OR OTHERWISE MADE AVAILABLE TO AND SHOULD NOT BE OFFERED, SOLD OR OTHERWISE MADE AVAILABLE TO ANY RETAIL INVESTOR IN THE UNITED KINGDOM (THE UK). FOR THESE PURPOSES, A RETAIL INVESTOR MEANS A PERSON WHO IS ONE (OR MORE) OF: (I) A RETAIL CLIENT AS DEFINED IN POINT (8) OF ARTICLE 2 OF REGULATION (EU) NO 2017/565 AS IT FORMS PART OF DOMESTIC LAW BY VIRTUE OF THE EUROPEAN UNION (WITHDRAWAL) ACT 2018 (EUWA); (II) A CUSTOMER WITHIN THE MEANING OF THE PROVISIONS OF THE FSMA AND ANY RULES OR REGULATIONS MADE UNDER THE FSMA TO IMPLEMENT DIRECTIVE (EU) 2016/97, WHERE THAT CUSTOMER WOULD NOT QUALIFY AS A PROFESSIONAL CLIENT, AS DEFINED IN POINT (8) OF ARTICLE 2(1) OF REGULATION (EU) NO 600/2014 AS IT FORMS PART OF DOMESTIC LAW BY VIRTUE OF THE EUWA. CONSEQUENTLY, NO KEY INFORMATION DOCUMENT REQUIRED BY REGULATION (EU) NO 1286/2014 AS IT FORMS PART OF DOMESTIC LAW BY VIRTUE OF THE EUWA (THE UK PRIIPS REGULATION) FOR OFFERING OR SELLING THE COVERED BONDS OR OTHERWISE MAKING THEM AVAILABLE TO RETAIL INVESTORS IN THE UK HAS BEEN PREPARED AND THEREFORE

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OFFERING OR SELLING THE COVERED BONDS OR OTHERWISE MAKING THEM AVAILABLE TO ANY RETAIL INVESTOR IN THE UK MAY BE UNLAWFUL UNDER THE UK PRIIPS REGULATION.

Confirmation of your Representation: In order to be eligible to view this Supplement or make an investment decision with respect to the securities, investors must be either (1) "qualified institutional buyers" (QIBs) within the meaning of Rule 144A (Rule 144A) under the Securities Act or (2) non-US persons (within the meaning of Regulation S under the Securities Act) outside the US; provided that investors resident in a Member State of the EEA must be a qualified investor as defined in Regulation (EU) 2017/1129 (the Prospectus Regulation) and investors resident in the UK must be a qualified investor as defined in Regulation (EU) 2017/1129 as it forms part of the domestic law by virtue of the European Union (Withdrawal) Act 2018 (as amended by the European Union (Withdrawal Agreement) Act 2020) as amended, varied, superseded or substituted from time to time (EUWA) (the UK Prospectus Regulation). This Supplement is being sent at your request and by accepting the e-mail and accessing this Supplement, you shall be deemed to have represented to us that (1) you and any customers you represent are either (a) a QIB or (b) not a US person and that the electronic mail address that you gave us and to which this Supplement has been delivered is not located in the US (and if you are resident in a Member State of the EEA or the UK, you are a qualified investor as defined in the Prospectus Regulation or the UK Prospectus Regulation, as applicable) and (2) you consent to the delivery of this Supplement by electronic transmission.

You are reminded that this Supplement has been delivered to you on the basis that you are a person into whose possession this Supplement may be lawfully delivered in accordance with the laws of the jurisdiction in which you are located and you may not, nor are you authorised to, deliver this Supplement to any other person.

The materials relating to the offering do not constitute, and may not be used in connection with, an offer or solicitation in any place where offers or solicitations are not permitted by law. If a jurisdiction requires that the offering be made by a licenced broker or dealer and the relevant Dealer (as defined in the Supplement) or any affiliate of such Dealer is a licenced broker or dealer in that jurisdiction, the offering shall be deemed to be made by the Dealer or such affiliate on behalf of the Issuer (as defined in the Supplement) in such jurisdiction.

This Supplement has been sent to you in an electronic form. You are reminded that documents transmitted via this medium may be altered or changed during the process of electronic transmission and consequently none of Nationwide Building Society or any other Dealer appointed from time to time (nor any person who controls it nor any director, officer, employee nor agent of it or affiliate of any such person) accepts any liability or responsibility whatsoever in respect of any difference between the Supplement distributed to you in electronic format and the hard copy version available to you on request from Nationwide Building Society.

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SUPPLEMENT DATED 14 DECEMBER 2022 TO THE BASE PROSPECTUS REFERRED TO BELOW

NATIONWIDE BUILDING SOCIETY

(incorporated in England and Wales under the Building Societies Act 1986, as amended)

Issuer Legal Entity Identifier (LEI): 549300XFX12G42QIKN82

€45 billion

Global Covered Bond Programme

unconditionally and irrevocably guaranteed as to payments by

Nationwide Covered Bonds LLP

(a limited liability partnership incorporated in England and Wales)

This supplement (the Supplement) to the base prospectus dated 2 September 2022, as supplemented by the supplementary prospectus dated 18 November 2022 (the Base Prospectus) constitutes a supplementary prospectus for the purposes of Section 87G of the Financial Services and Markets Act 2000 and is prepared in connection with the €45 billion covered bond programme (the Programme) established by Nationwide Building Society (the Issuer or Nationwide) unconditionally and irrevocably guaranteed as to payments by Nationwide Covered Bonds LLP (the LLP). Terms defined in the Base Prospectus have the same meaning when used in this Supplement.

This Supplement is supplemental to, and should be read in conjunction with, the Base Prospectus and any other supplements to the Base Prospectus issued by the Issuer.

The Covered Bonds and the Covered Bond Guarantee have not been and will not be registered under the US Securities Act of 1933, as amended (the Securities Act), or under the applicable securities laws or the regulations of any state of the United States, and may not be offered, sold or delivered in the United States or to, or for the benefit of, US persons (as defined in Regulation S (Regulation S) under the Securities Act) except pursuant to an exemption from, or in a transaction not subject to, the registration requirements of the Securities Act. The Covered Bonds are being offered (a) outside the United States to non-US persons in reliance on Regulation S and (b) in the case of Registered Covered Bonds only, within the United States only to "qualified institutional buyers" (QIBs) (as defined in Rule 144A under the Securities Act (Rule 144A)) in compliance with Rule 144A or in other transactions exempt from registration under the Securities Act. Registered Covered Bonds are subject to certain restrictions on transfer.

Each purchaser of a Covered Bond will be deemed, by its acceptance or purchase thereof, to have made certain acknowledgements, representations and agreements intended to restrict the resale or other transfer of such Covered Bond, as described in the Base Prospectus, and, in connection therewith, may be required to provide confirmation of its compliance with such resale and other transfer restrictions in certain cases (see "Subscription and Sale and Transfer and Selling Restrictions" in the Base Prospectus).

This Supplement has been approved as a supplement by the Financial Conduct Authority (the FCA, known before 1 April 2013 as the Financial Services Authority (the FSA), as competent authority under Regulation (EU) 2017/1129 as it forms part of domestic law by virtue of the European Union (Withdrawal) Act 2018 (EUWA) (the UK Prospectus Regulation). The FCA only approves this Supplement as meeting the standards of completeness, comprehensibility and consistency imposed by the UK Prospectus Regulation. Such approval should not be considered as an endorsement of the issuer

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or the quality of the Covered Bonds that are subject of this Supplement and investors should make their own assessment as to the suitability of investing in the Covered Bonds.

The Issuer accepts responsibility for the information contained in this Supplement. To the best of the knowledge of the Issuer (having taken all reasonable care to ensure that such is the case) the information contained in this Supplement is in accordance with the facts and does not omit anything likely to affect the import of such information.

Purpose of this Supplement

The purpose of this Supplement is to:

1. update the "Risk Factors" section;
2. update the "Capitalisation and Indebtedness" section;
3. update the "Management's Discussion and Analysis of Financial Condition and Results of Operations" section;
4. update the "Business of the Society" section;
5. update the "Selected Statistical Information" section;
6. update the "Management" section; and
7. update the "Supervision and Regulation" section.

To the extent that there is any inconsistency between (a) any statement in this Supplement or any statement incorporated by reference into the Base Prospectus by this Supplement and (b) any other statement in or incorporated by reference in the Base Prospectus, the statements in (a) above will prevail.

If documents which are incorporated by reference to this Supplement themselves incorporate any information or other documents therein, either expressly or implicitly, such information or other documents will not form part of this Supplement for the purposes of the Prospectus Regulation except where such information or other documents are specifically incorporated by reference to the Supplement.

Copies of this Supplement, the Base Prospectus and all documents which are incorporated by reference in the Base Prospectus are available at https://www.nationwide.co.uk/investor-relations/.

Save as disclosed in this Supplement and the supplementary prospectus dated 18 November 2022, there has been no other significant new factor, material mistake or material inaccuracy relating to information included in the Base Prospectus since the publication of the Base Prospectus.

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This section should be read together with the sections titled "Risk Factors" in the Base Prospectus.

RISK FACTORS

The following supplements "Risk Factors - Economic and Financial Risks - The UK economy" in the Base Prospectus.

The UK economy

The Issuer's business and prospects are largely driven by the UK mortgage, savings and personal current account markets and the level of interest rates, which in turn are driven by the UK economy, the outlook for which is inherently uncertain. Consequently, the Issuer is subject to inherent risks arising from general economic conditions in the UK but also indirect risks arising from volatility in global financial markets in the Eurozone and elsewhere.

The Issuer offers a range of banking and financial products and services to UK retail customers with its business activities concentrated in the UK retail deposit and residential mortgage markets. Under current building society legislation, the Issuer's ability to diversify its business is limited. Accordingly, a decline in the UK economy or the predominantly retail markets in which the Issuer operates could have a material adverse impact on its financial performance and business operations. The Issuer is also directly and indirectly subject to inherent risks arising from general economic conditions in the UK, global macro-economic conditions and geopolitical conditions in the Issuer's economies, particularly the Eurozone.

Domestic and international conditions are subject to fluctuations which can adversely affect the Issuer's operating performance, financial conditions and/or prospects, through a wide range of potential channels, including but not limited to; changes in unemployment levels, rates of inflation, level of interest rates, consumer confidence, the state of the UK housing market (including house prices), counterparty risk and the availability and cost of credit in wholesale and retail markets.

Such fluctuations can occur as a result of different types of shocks, which in recent years have included global financial crises, the Covid-19 pandemic and increased geopolitical tensions and conflict. Furthermore, potential sources of future shocks are many and varied and often difficult to foresee in advance.

Economic conditions may also be affected by long-term structural changes such as demographic shifts and/or climate change, as well as by changes to government or regulatory policies domestically or globally. The latter may include significant changes to monetary, fiscal or macro-prudential policies which could have a negative impact on the Issuer's markets or wider economic conditions. Political uncertainty and/or significant changes to government policy could also affect the Issuer's markets and/or wider economic prospects. For example, the UK's exit from the European Union is likely to have implications for the UK's trading relationships and wider economic performance for many years to come. These fluctuations, future shocks and long-term structural changes may have an adverse impact on the Issuer's operating performance, financial conditions and/or prospects.

In addition, there has been significant market turbulence following the Government "mini-Budget" announcement in late September 2022. Sterling fell to all-time lows against the dollar while swap rates surged. The market volatility was triggered by investor unease at the prospect of large unfunded tax cuts that weaken the public finances and entail a significant increase in gilt supply at a time when the Bank of England is raising its Bank Rate in response to high inflation and is due to start reducing the size of its balance sheet by selling government bonds. The volatility was exacerbated by the emergence of financial strains at some UK pension funds, which was triggered by the sharp increase in gilt yields, and prompted the Bank of England to intervene in the long dated gilt market for a period due to financial stability concerns. The economic outlook remains highly uncertain, with increases in the cost of living

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