TERMS AGREEMENT

Exhibit 1.01

TERMS AGREEMENT

January 5, 2016

Citigroup Inc.

399 Park Avenue

New York, New York 10022

Attention: Deputy Treasurer

Ladies and Gentlemen:

We understand that Citigroup Inc., a Delaware corporation (the “Company”), proposes to issue and sell US $2,000,000,000 aggregate principal amount of its debt securities (the “Securities”). Subject to the terms and conditions set forth herein or incorporated by reference herein, we, Citigroup Global Markets Inc., BBVA Securities Inc., Credit Suisse Securities (USA) LLC, Deutsche Bank Securities Inc., HSBC Securities (USA) Inc., ING Financial Markets LLC, Natixis Securities Americas LLC, Scotia Capital (USA) Inc., TD Securities (USA) LLC, ABN AMRO Securities (USA) LLC, ANZ Securities, Inc., Blaylock Beal Van, LLC, CastleOak Securities, L.P., CIBC World Markets Corp., Commerz Markets LLC, Credit Agricole Securities (USA) Inc., Danske Markets Inc., Drexel Hamilton, LLC, Lebenthal & Co., LLC, Lloyds Securities Inc., Loop Capital Markets LLC, MFR Securities, Inc., Mischler Financial Group, Inc., Mitsubishi UFJ Securities (USA), Inc., nabSecurities, LLC, National Bank of Canada Financial Inc., PNC Capital Markets LLC, Standard Chartered Bank, UBS Securities LLC, Wells Fargo Securities, LLC and The Williams Capital Group, L.P., as underwriters (the “Underwriters”), offer to purchase, severally and not jointly, the principal amount of the Securities set forth opposite our respective names on the list attached as Annex A hereto at 99.442% of the principal amount thereof, plus accrued interest, if any, from the date of issuance. The Closing Date shall be January 12, 2016, at 9:30 a.m. (Eastern Time). The closing shall take place at the offices of Cleary Gottlieb Steen & Hamilton LLP located at One Liberty Plaza, New York, New York 10006.

The Securities shall have the following terms:

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Additional Terms:

The Securities shall be issuable as Registered Securities only. The Securities will be initially represented by one or more global Securities registered in the name of The Depository Trust Company (“DTC”) or its nominees, as described in the Prospectus relating to the Securities. Beneficial interests in the Securities will be shown on, and transfers thereof will be effected only through, records maintained by DTC, Euroclear Bank S.A./N.V. and Clearstream International and their respective participants. Owners of beneficial interests in the Securities will be entitled to physical delivery of Securities in certificated form only under the limited circumstances described in the Prospectus. Principal and interest on the Securities shall be payable in United States dollars. Sections 12.02 and 12.03 of the indenture, dated as of November 13, 2013, between the Company and The Bank of New York Mellon, as trustee (the “Trustee”) (the “Indenture”) relating to defeasance and discharge and covenant defeasance, respectively, shall apply to the Securities.

All the provisions contained in the document entitled “Citigroup Inc. — Debt Securities — Underwriting Agreement — Basic Provisions” and dated March 2, 2006 (the “Basic Provisions”), a copy of which you have previously received, are herein incorporated by reference in their entirety and shall be deemed to be a part of this Terms Agreement to the same extent as if the Basic Provisions had been set forth in full herein, except for:

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Terms defined in the Basic Provisions are used herein as therein defined. The Execution Time means 3:15 p.m. (Eastern Time).

The Company agrees to use its best efforts to have the Securities approved for listing on the regulated market of the Luxembourg Stock Exchange and to maintain such listing so long as any of the Securities are outstanding; provided, however, that if it is impracticable or unduly burdensome, in the good faith determination of the Company, to maintain such listing due to changes in applicable law or listing requirements occurring after the original issue date of the Securities, the Company may de-list the Securities from the regulated market of the Luxembourg Stock Exchange and shall use its reasonable best efforts to obtain an alternative admission to listing, trading and/or quotation of the Securities by another listing authority, exchange or system within or outside the European Union as it may decide. If such an alternative admission is not available or is, in the Company’s opinion, unduly burdensome, such an alternative admission will not be obtained, and the Company shall have no further obligation in respect of any listing, trading or quotation for the Securities.

The Underwriters hereby agree in connection with the underwriting of the Securities to comply with the requirements set forth in any applicable sections of Rule 5121 of the Financial Industry Regulatory Authority, Inc.

Selling Restrictions:

European Economic Area

Each Underwriter represents and agrees that in relation to each Member State of the European Economic Area which has implemented the Prospectus Directive (each, a “Relevant Member State”), with effect from and including the date on which the Prospectus Directive is implemented in that Relevant Member State (the “Relevant Implementation Date”) it has not made and will not make an offer to the public of Securities which are the subject of the offering contemplated by this Terms Agreement in that Relevant Member State except that it may, with effect from and including the Relevant Implementation Date, make an offer to the public in that Relevant Member State:

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provided that no such offer of Securities referred to in (a) to (c) above shall require the Company or any Underwriter to publish a prospectus pursuant to Article 3 of the Prospectus Directive or supplement a prospectus pursuant to Article 16 of the Prospectus Directive.

For the purposes of this provision, the expression an “offer to the public” in relation to any Securities in any Relevant Member State means the communication in any form and by any means of sufficient information on the terms of the offer and the Securities to be offered so as to enable an investor to decide to purchase, as the same may be varied in that Member State by any measure implementing the Prospectus Directive in that Member State and the expression “Prospectus Directive” means Directive 2003/71/EC (as amended, including by Directive 2010/73/EU), and includes any relevant implementing measure in each Relevant Member State.

This EEA selling restriction is in addition to any other selling restrictions set out below.

United Kingdom

Each Underwriter represents and agrees that the Prospectus Supplement and accompanying Prospectus relating to this offering is only being distributed to, and is only directed at, persons in the United Kingdom that are qualified investors within the meaning of Article 2(1)(e) of the Prospectus Directive that are also (i) investment professionals falling within Article 19(5) of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2005 (the “Order”) or (ii) high net worth entities, and other persons to whom it may lawfully be communicated, falling within Article 49(2)(a) to (d) of the Order (all such persons together being referred to as “Relevant Persons”).

France

No prospectus (including any amendment, supplement or replacement thereto) has been prepared in connection with the offering of the Securities that has been approved by the Autorité des marchés financiers or by the competent authority of another State that is a contracting party to the Agreement on the European Economic Area and notified to the Autorité des marchés financiers; each Underwriter represents and agrees that no Securities have been offered or sold nor will be offered or sold, directly or indirectly, to the public in France; each Underwriter represents and agrees that the prospectus or any other offering material relating to the Securities have not been distributed or caused to be distributed and will not be distributed or caused to be distributed to the public in France; such offers, sales and distributions have been and shall only be made in France to persons licensed to provide the investment service of portfolio management for the account of third parties, qualified investors (investisseurs qualifiés) and/or a restricted circle of investors (cercle restreint d’investisseurs), in each case investing for their own account, all as defined in Articles L. 411-2, D. 411-1, D. 411-2, D. 411-4, D. 734-1, D.744-1, D. 754-1 and D. 764-1 of the Code monétaire et financier. Each Underwriter represents and agrees that the direct or indirect distribution to the public in France of any so acquired Securities may be made only as provided by Articles L. 411-1, L. 411-2, L. 412-1 and L. 621-8 to L. 621-8-3 of the Code monétaire et financier and applicable regulations thereunder.

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Hong Kong

Each Underwriter:

(a) has not offered or sold and will not offer or sell in Hong Kong, by means of any document, any Securities other than to (i) “professional investors” as defined in the Securities and Futures Ordinance (Cap. 571) of Hong Kong and any rules made under that Ordinance; or (ii) in other circumstances which do not result in the document being a “prospectus” as defined in the Companies Ordinance (Cap. 32) of Hong Kong or which do not constitute an offer to the public within the meaning of that Ordinance; and

(b) has not issued or had in its possession for the purposes of issue, and will not issue or have in its possession for the purposes of issue, whether in Hong Kong or elsewhere, any advertisement, invitation or document relating to the Securities, which is directed at, or the contents of which are or are likely to be accessed or read by, the public in Hong Kong (except if permitted to do so under securities laws of Hong Kong) other than with respect to Securities which are or are intended to be disposed of only to persons outside Hong Kong or only to “professional investors” within the meaning of the Securities and Futures Ordinance (Cap. 571) of Hong Kong and any rules made under that Ordinance.

Japan

The Securities have not been and will not be registered under the Financial Instruments and Exchange Law of Japan (the “FIEA”). Each Underwriter represents and agrees that it has not and will not offer or sell, directly or indirectly, any of the Securities in Japan or to, or for the account or benefit of, any resident of Japan (including any corporation or other entity organized under the laws of Japan), or to, or for the account or benefit of, any resident of Japan for reoffering or resale, directly or indirectly, in Japan or to, or for the account or benefit of, any resident of Japan except (1) pursuant to an exemption from the registration requirements of, or otherwise in compliance with, the FIEA and (2) in compliance with the other applicable laws, regulations and governmental guidelines of Japan.

Singapore

The Prospectus Supplement and accompanying Prospectus relating to this offering have not been and will not be registered as a prospectus with the Monetary Authority of Singapore under the Securities and Futures Act (Chapter 289 of Singapore) (the “SFA”). Accordingly, each Underwriter has not offered or sold any Securities or caused the Securities to be made the subject of an invitation for subscription or purchase and will not offer or sell any Securities or cause the Securities to be made the subject of an invitation for subscription or purchase, and has not circulated or distributed, nor will it circulate or distribute, such Prospectus Supplement and accompanying Prospectus or any other document or material in connection with the offer or sale, or invitation for subscription or purchase, of the Securities, whether directly or indirectly, to persons in Singapore other than (i) to an institutional investor under Section 274 of the SFA, (ii) to a Relevant Person, or any person pursuant to Section 275(1A), and in accordance with the conditions, specified in Section 275 of the SFA or (iii) otherwise pursuant to, and in accordance with the conditions of, any other applicable provision of the SFA.

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Each Underwriter will notify (whether through the distribution of the Prospectus Supplement and accompanying Prospectus relating to this offering or otherwise) each of the following Relevant Persons specified in Section 275 of the SFA which has subscribed or purchased Securities from or through that Underwriter, namely a person which is:

(a) a corporation (which is not an accredited investor (as defined in Section 4A of the SFA)) the sole business of which is to hold investments and the entire share capital of which is owned by one or more individuals, each of whom is an accredited investor; or

(b) a trust (where the trustee is not an accredited investor) whose sole purpose is to hold investments and each beneficiary is an accredited investor, that shares, debentures and units of shares and debentures of that corporation or the beneficiaries’ rights and interest in that trust shall not be transferable for 6 months after that corporation or that trust has acquired the Securities under Section 275 of the SFA except:

(1) to an institutional investor (for corporations, under Section 274 of the SFA) or to a Relevant Person defined in Section 275(2) of the SFA, or to any person pursuant to an offer that is made on terms that such shares, debentures and units of shares and debentures of that corporation or such rights and interest in that trust are acquired at a consideration of not less than $200,000 (or its equivalent in a foreign currency) for each transaction, whether such amount is to be paid for in cash or by exchange of securities or other assets, and further for corporations, in accordance with the conditions specified in Section 275 of the SFA; or

(2) where no consideration is given for the transfer; or

(3) by operation of law.

In addition to the legal opinions required by Sections 6(b) and 6(c) of the Basic Provisions, the Underwriters shall have received an opinion of Skadden, Arps, Slate, Meagher & Flom LLP, counsel to the Company, dated the Closing Date, to the effect that although the discussion set forth in the Prospectus under the headings “United States Federal Income Tax Considerations – Introduction” and “– Non-United States Holders” and in the final three paragraphs under the heading “Description of Notes” in the Prospectus Supplement dated January 5, 2016, does not purport to discuss all possible United States federal income tax consequences of the purchase, ownership and disposition of the Securities to non-United States holders of the Securities, such discussion constitutes, in all material respects, a fair and accurate summary of the United States federal income tax consequences of the ownership and disposition of the Securities to non-United States holders of the Securities.

Barbara Politi, Esq., Assistant General Counsel – Capital Markets of the Company, is counsel to the Company. Skadden, Arps, Slate, Meagher & Flom LLP has also acted as counsel to the Company in connection with matters related to the issuance of the Securities. Cleary Gottlieb Steen & Hamilton LLP is counsel to the Underwriters.

Please accept this offer no later than 9:00 p.m. (Eastern Time) on January 5, 2016 by signing a copy of this Terms Agreement in the space set forth below and returning the signed copy to us, or by sending us a written acceptance in the following form:

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“We hereby accept your offer, set forth in the Terms Agreement, dated January 5, 2016, to purchase the Securities on the terms set forth therein.”

ANNEX A

ANNEX B

FINAL TERM SHEET

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This Note is a Global Security within the meaning of the Indenture hereinafter referred to and is registered in the name of the Depository named below or a nominee of the Depository. This Note is not exchangeable for Notes registered in the name of a Person other than the Depository or its nominee except in the limited circumstances described herein and in the Indenture, and no transfer of this Note (other than a transfer of this Note as a whole by the Depository to a nominee of the Depository or by a nominee of the Depository to the Depository or another nominee of the Depository) may be registered except in the limited circumstances described herein.

Unless this certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (the “Depository”), to the Company or its agent for registration of transfer, exchange, or payment, and any certificate issued is registered in the name of Cede & Co. or in such other name as is requested by an authorized representative of the Depository (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of the Depository), ANY TRANSFER, PLEDGE, OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein.

CITIGROUP INC.

3.700% Notes due January 12, 2026

CITIGROUP INC., a Delaware corporation (the “Company”, which term includes any successor Person under the Indenture), for value received, hereby promises to pay to Cede & Co., or registered assigns, the principal sum of $500,000,000 on January 12, 2026 and to pay interest thereon from and including January 12, 2016 or from the most recent Interest Payment Date to which interest has been paid or duly provided for, semi-annually, on January 12 and July 12 of each year, commencing July 12, 2016 at the rate of 3.700% per annum, until the principal hereof is paid or made available for payment. The interest so payable, and punctually paid or duly provided for, on any Interest Payment Date will, as provided in the Indenture, be paid to the Person in whose name this Note is registered at the close of business on the Record Date for such interest, which shall be the Business Day immediately preceding such Interest Payment Date.

Any such interest not so punctually paid or duly provided for will forthwith cease to be payable to the holder on such Record Date and may either be paid to the Person in whose name this Note is registered at the close of business on a subsequent Record Date, such subsequent Record Date to be not less than ten days prior to the date of payment of such defaulted interest, notice whereof shall be given to holders of Notes of this series not less than ten days prior to such subsequent Record Date, or be paid at any time in any other lawful manner not inconsistent with the requirements of any securities exchange on which the Notes of this series may be listed, and upon such notice as may be required by such exchange, all as more fully provided in the Indenture.

Interest hereon will be calculated on the basis of a 360-day year comprised of twelve 30-day months.

If either an Interest Payment Date or the Maturity of the Notes falls on a day that is not a Business Day, such Interest Payment Date or Maturity will be the next succeeding Business Day, and no further interest will accrue in respect of such postponement. If a date for payment of interest or principal on the Notes falls on a day that is not a business day in the place of payment, such payment will be made on the next succeeding business day in such place of payment as if made on the date the payment was due. No interest will accrue on any amounts payable for the period from and after the due date for payment of such principal or interest. For these purposes, “Business Day” means any day which is a day on which commercial banks settle payments and are open for general business in The City of New York.

Payment of the principal of and interest on this Note will be made at the office or agency of the Trustee maintained for that purpose in The City of New York.

Reference is hereby made to the further provisions of this Note set forth on the reverse hereof, which further provisions shall for all purposes have the same effect as if set forth at this place.

Unless the certificate of authentication hereon has been executed by the Trustee or by an authenticating agent on behalf of the Trustee by manual signature, this Note shall not be entitled to any benefit under the Indenture or be valid or obligatory for any purpose.

IN WITNESS WHEREOF, the Company has caused this instrument to be duly executed under its corporate seal.

Dated: January 12, 2016

This is one of the Notes of the series issued under the within-mentioned Indenture.

Dated: January 12, 2016