ADECCO : LAUNCHES ACCELERATED BOOKBUILD TO RAISE UP TO EUR 230 MILLION

This announcement is not a prospectus and not an offer of securities for sale in any jurisdiction, including in or into the United States, Canada, Australia or Japan.

AD HOC Announcement pursuant to Art. 53 LR

Zurich, Switzerland, 7 September 2021

ADECCO GROUP LAUNCHES ACCELERATED BOOKBUILD TO RAISE UP TO EUR 230 MILLION

Adecco Group AG (the "Company" or "Adecco Group") today launches the placement of up to 7,500,000 newly issued shares, each with a par value of CHF 0.10 (the "New Shares"), sourced from existing authorised capital excluding existing shareholders' pre-emptive rights, via an accelerated bookbuilding.

The New Shares will be offered by way of a private placement exclusively to professional investors in Switzerland, outside of Switzerland and the United States to institutional investors (in reliance on Regulation S under the U.S. Securities Act of 1933) and in the United States to qualified institutional buyers (in reliance on Rule 144A under the U.S. Securities Act).

The New Shares carry full dividend rights for the fiscal year 2021 beginning on 1 January 2021.

Adecco Group intends to use the net proceeds from the Capital Increase to fund, in part, the acquisition of AKKA Technologies, which was announced on 28 July 2021. For further information on this transaction, please click here.

The placement price of the New Shares will be determined in the accelerated bookbuilding process and is expected to be published no later than tomorrow morning prior to market opening.

The New Shares are expected to be listed and admitted to trading on the SIX Swiss Exchange on 9 September 2021. The first day of trading is expected to be 9 September 2021.

Adecco Group has agreed to a lock-up period of 90 days from the Settlement Date, subject to customary exceptions.

About the Adecco Group

The Adecco Group is the world's leading talent advisory and solutions company. We believe in making the future work for everyone, and every day enable more than 3.5 million careers. We skill, develop and hire talent in 57 countries, enabling organisations to embrace the future of work. As a Fortune Global 500 company, we lead by example, creating shared value that fuels economies and builds better societies. Our culture of inclusivity, entrepreneurship and teamwork empowers our 30,000 employees. We are proud to have been consistently ranking as one of the "World's Best Workplaces" by Great Place to Work®. The Group is headquartered in Zurich, Switzerland (ISIN: CH0012138605) and listed on the SIX Swiss Exchange (ADEN).

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For further information please contact:

Investor Relations	Press Office
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Disclaimer

THE CONTENTS OF THIS ANNOUNCEMENT HAVE BEEN PREPARED BY AND ARE THE SOLE RESPONSIBILITY OF ADECCO GROUP AG (THE "COMPANY").

THE INFORMATION CONTAINED IN THIS ANNOUNCEMENT IS FOR BACKGROUND PURPOSES ONLY AND DOES NOT PURPORT TO BE FULL OR COMPLETE. NO RELIANCE MAY BE PLACED BY ANY PERSON FOR ANY PURPOSE ON THE INFORMATION CONTAINED IN THIS ANNOUNCEMENT OR ITS ACCURACY, FAIRNESS OR COMPLETENESS.

THIS INFORMATION DOES NOT CONSTITUTE AN OFFER OR INVITATION TO SUBSCRIBE FOR OR PURCHASE ANY SECURITIES TO ANY PERSON IN SWITZERLAND, THE UNITED STATES, AUSTRALIA, CANADA, JAPAN OR IN ANY JURISDICTION TO WHOM OR IN WHICH SUCH OFFER OR SOLICITATION IS UNLAWFUL. IT IS NOT BEING ISSUED IN COUNTRIES WHERE THE PUBLIC DISSEMINATION OF THE INFORMATION CONTAINED HEREIN MAY BE RESTRICTED OR PROHIBITED BY LAW. THE DISTRIBUTION OF THIS ANNOUNCEMENT MAY BE RESTRICTED BY LAW IN CERTAIN JURISDICTIONS AND PERSONS INTO WHOSE POSSESSION ANY DOCUMENT OR OTHER INFORMATION REFERRED TO HEREIN COMES SHOULD INFORM THEMSELVES ABOUT AND OBSERVE SUCH RESTRICTION. ANY FAILURE TO COMPLY WITH THESE RESTRICTIONS MAY CONSTITUTE A VIOLATION OF THE SECURITIES LAWS OF ANY SUCH JURISDICTION. SECURITIES OF THE COMPANY ARE NOT BEING PUBLICLY OFFERED. IN PARTICULAR, THE SECURITIES REFERRED TO HEREIN HAVE NOT BEEN AND WILL NOT BE REGISTERED UNDER THE US SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), AND MAY NOT BE OFFERED OR SOLD IN THE UNITED STATES UNLESS THE SECURITIES ARE REGISTERED UNDER THE SECURITIES ACT, OR AN EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT IS AVAILABLE. THE ISSUER OF THE SECURITIES HAS NOT REGISTERED, AND DOES NOT INTEND TO REGISTER, ANY PORTION OF THE OFFERING OR SECURITIES IN THE UNITED STATES AND DOES NOT INTEND TO CONDUCT A PUBLIC OFFERING OF SECURITIES IN THE UNITED STATES. THE SECURITIES REFERRED TO HEREIN HAVE NOT BEEN AND WILL NOT BE REGISTERED UNDER THE APPLICABLE SECURITIES LAWS OF AUSTRALIA, CANADA OR JAPAN. SUBJECT TO CERTAIN EXCEPTIONS, THE SECURITIES REFERRED TO HEREIN MAY NOT BE OFFERED, SOLD OR DELIVERED WITHIN THE UNITED STATES, EXCEPT IN AN "OFFSHORE TRANSACTION" IN ACCORDANCE WITH REGULATION S UNDER THE SECURITIES ACT, OR FOR THE ACCOUNT OR BENEFIT OF ANY NATIONAL, RESIDENT OR CITIZEN OF AUSTRALIA, CANADA OR JAPAN. THIS ANNOUNCEMENT QUALIFIES AS ADVERTISEMENT AND CONSTITUTES NEITHER AN OFFER TO SELL NOR A SOLICITATION TO BUY SECURITIES OF THE COMPANY AND IT DOES NOT CONSTITUTE A PROSPECTUS OR SIMILAR DOCUMENT OR NOTICE WITHIN THE MEANING OF ARTICLES 35 ET SEQQ. AND 69 OF THE SWISS FINANCIAL SERVICES ACT. THE SECURITIES ARE OFFERED AND ADMITTED TO TRADING AND LISTED WITHOUT THE PUBLICATION OF A PROSPECTUS IN RELIANCE ON THE EXEMPTIONS PROVIDED FOR BY THE FINANCIAL SERVICES ACT.

IN EACH MEMBER STATE OF THE EUROPEAN ECONOMIC AREA AND THE UNITED KINGDOM (EACH, A "RELEVANT STATE"). THIS ANNOUNCEMENT AND ANY OFFER IF MADE SUBSEQUENTLY IS DIRECTED ONLY AT PERSONS WHO ARE "QUALIFIED INVESTORS" WITHIN THE MEANING OF, IN THE CASE OF THE EUROPEAN ECONOMIC AREA, THE PROSPECTUS REGULATION (REGULATION (EU) 2017/1129), OR, IN THE CASE OF THE UNITED KINGDOM, OF REGULATION (EU) 2017/1129 AS IT FORMS PART OF DOMESTIC LAW IN THE UNITED KINGDOM BY VIRTUE OF THE EUROPEAN UNION (WITHDRAWAL) ACT 2018 ("QUALIFIED INVESTORS"). THIS ANNOUNCEMENT IS BEING DISTRIBUTED ONLY TO, AND IS DIRECTED ONLY AT (I) PERSONS OUTSIDE THE UNITED KINGDOM, (II) PERSONS WHO HAVE PROFESSIONAL EXPERIENCE IN MATTERS RELATING TO INVESTMENTS FALLING WITHIN ARTICLE 19(5) OF THE FINANCIAL SERVICES AND MARKETS ACT 2000 (FINANCIAL PROMOTION) ORDER 2005 (THE "ORDER") OR (III) HIGH NET WORTH ENTITIES, AND OTHER PERSONS TO WHOM IT MAY OTHERWISE LAWFULLY BE COMMUNICATED, FALLING WITHIN ARTICLE 49(2) OF THE ORDER (ALL SUCH PERSONS TOGETHER BEING REFERRED TO AS "RELEVANT PERSONS"). ANY INVESTMENT OR INVESTMENT ACTIVITY TO WHICH THIS COMMUNICATION RELATES IS AVAILABLE ONLY TO RELEVANT PERSONS AND WILL BE ENGAGED ONLY WITH RELEVANT PERSONS. ANY PERSON, WHO IS NOT A RELEVANT PERSON, MUST NOT ACT OR RELY ON THIS COMMUNICATION OR ANY OF ITS CONTENTS.

THIS ANNOUNCEMENT MAY INCLUDE STATEMENTS THAT ARE, OR MAY BE DEEMED TO BE, "FORWARD-LOOKING STATEMENTS". THESE FORWARD-LOOKING STATEMENTS MAY BE IDENTIFIED BY THE USE OF FORWARD-LOOKING TERMINOLOGY, INCLUDING THE TERMS "BELIEVES", "ESTIMATES", "PLANS", "PROJECTS", "ANTICIPATES", "EXPECTS", "INTENDS", "MAY", "WILL" OR "SHOULD" OR, IN EACH CASE, THEIR NEGATIVE OR OTHER VARIATIONS OR COMPARABLE TERMINOLOGY, OR BY DISCUSSIONS OF STRATEGY, PLANS, OBJECTIVES, GOALS, FUTURE EVENTS OR INTENTIONS. FORWARD-LOOKING STATEMENTS MAY AND OFTEN DO DIFFER MATERIALLY FROM ACTUAL RESULTS. ANY FORWARD-LOOKING STATEMENTS REFLECT THE COMPANY'S CURRENT VIEW WITH RESPECT TO FUTURE EVENTS AND ARE SUBJECT TO RISKS RELATING TO FUTURE EVENTS AND OTHER RISKS, UNCERTAINTIES AND ASSUMPTIONS RELATING TO THE GROUP'S BUSINESS, RESULTS OF OPERATIONS, FINANCIAL POSITION, LIQUIDITY, PROSPECTS, GROWTH OR STRATEGIES. FORWARD-LOOKING STATEMENTS SPEAK ONLY AS OF THE DATE THEY ARE MADE.

EACH OF THE COMPANY, THE BANKING SYNDICATE AND THEIR RESPECTIVE AFFILIATES EXPRESSLY DISCLAIMS ANY OBLIGATION OR UNDERTAKING TO UPDATE, REVIEW OR REVISE ANY FORWARD LOOKING STATEMENT CONTAINED IN THIS ANNOUNCEMENT WHETHER AS A RESULT OF NEW INFORMATION, FUTURE DEVELOPMENTS OR OTHERWISE.

THE BANKING SYNDICATE ARE ACTING EXCLUSIVELY FOR COMPANY AND NO-ONE ELSE IN CONNECTION WITH THE OFFERING. THEY WILL NOT REGARD ANY OTHER PERSON AS THEIR RESPECTIVE CLIENTS IN RELATION TO THE OFFERING AND WILL NOT BE RESPONSIBLE TO ANYONE OTHER THAN THE

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COMPANY FOR PROVIDING THE PROTECTIONS AFFORDED TO THEIR RESPECTIVE CLIENTS, NOR FOR PROVIDING ADVICE IN RELATION TO THE OFFERING, THE CONTENTS OF THIS ANNOUNCEMENT OR ANY TRANSACTION, ARRANGEMENT OR OTHER MATTER REFERRED TO HEREIN.

IN CONNECTION WITH THE OFFERING, THE BANKING SYNDICATE AND ANY OF THEIR AFFILIATES MAY TAKE UP A PORTION OF THE SECURITIES IN THE OFFERING AS A PRINCIPAL POSITION AND IN THAT CAPACITY MAY RETAIN, PURCHASE, SELL, OFFER TO SELL FOR THEIR OWN ACCOUNTS SUCH SECURITIES AND OTHER SECURITIES OF THE ISSUER OR RELATED INVESTMENTS IN CONNECTION WITH THE OFFERING OR OTHERWISE. ACCORDINGLY, REFERENCES TO THE SECURITIES BEING ISSUED, OFFERED, SUBSCRIBED, ACQUIRED, PLACED OR OTHERWISE DEALT IN SHOULD BE READ AS INCLUDING ANY ISSUE OR OFFER TO, OR SUBSCRIPTION, ACQUISITION, PLACING OR DEALING BY THE BANKING SYNDICATE AND ANY OF THEIR AFFILIATES ACTING IN SUCH CAPACITY. IN ADDITION THE BANKING SYNDICATE, AND ANY OF THEIR AFFILIATES MAY ENTER INTO FINANCING ARRANGEMENTS (INCLUDING SWAPS, WARRANTS OR CONTRACTS FOR DIFFERENCES) WITH INVESTORS IN CONNECTION WITH WHICH THE BANKING SYNDICATE AND ANY OF THEIR AFFILIATES MAY FROM TIME TO TIME ACQUIRE, HOLD OR DISPOSE OF SECURITIES. THE BANKING SYNDICATE DO NOT INTEND TO DISCLOSE THE EXTENT OF ANY SUCH INVESTMENT OR TRANSACTIONS OTHERWISE THAN IN ACCORDANCE WITH ANY LEGAL OR REGULATORY OBLIGATIONS TO DO SO.

NONE OF THE BANKING SYNDICATE OR ANY OF THEIR RESPECTIVE DIRECTORS, OFFICERS, EMPLOYEES, ADVISERS OR AGENTS ACCEPTS ANY RESPONSIBILITY OR LIABILITY WHATSOEVER FOR OR MAKES ANY REPRESENTATION OR WARRANTY, EXPRESS OR IMPLIED, AS TO THE TRUTH, ACCURACY OR COMPLETENESS OF THE INFORMATION IN THIS ANNOUNCEMENT (OR WHETHER ANY INFORMATION HAS BEEN OMITTED FROM THE ANNOUNCEMENT) OR ANY OTHER INFORMATION RELATING TO THE COMPANY, ITS SUBSIDIARIES OR ASSOCIATED COMPANIES, WHETHER WRITTEN, ORAL OR IN A VISUAL OR ELECTRONIC FORM, AND HOWSOEVER TRANSMITTED OR MADE AVAILABLE OR FOR ANY LOSS HOWSOEVER ARISING FROM ANY USE OF THIS ANNOUNCEMENT OR ITS CONTENTS OR OTHERWISE ARISING IN CONNECTION THEREWITH.