Form of Global Note for the 3.050% Senior Notes due 2061

Exhibit 4.3

[Form of Note]

THIS SECURITY IS A GLOBAL SECURITY WITHIN THE MEANING OF THE INDENTURE HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF A DEPOSITORY (AS DEFINED IN THE INDENTURE) OR A NOMINEE THEREOF. THIS GLOBAL SECURITY IS EXCHANGEABLE FOR SECURITIES REGISTERED IN THE NAME OF A PERSON OTHER THAN THE DEPOSITORY OR ITS NOMINEE ONLY IN THE LIMITED CIRCUMSTANCES DESCRIBED IN THE INDENTURE AND, UNLESS AND UNTIL IT IS EXCHANGED IN WHOLE OR IN PART FOR SECURITIES IN DEFINITIVE FORM, THIS GLOBAL SECURITY MAY NOT BE TRANSFERRED EXCEPT 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, OR BY THE DEPOSITORY OR ANY SUCH NOMINEE TO A SUCCESSOR DEPOSITORY OR A NOMINEE OF SUCH SUCCESSOR DEPOSITORY.

UNLESS THIS SECURITY IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION (“DTC”), TO THE COMPANY (AS DEFINED BELOW) OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY SECURITY ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR IN SUCH OTHER NAME AS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC) 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.

Chubb INA Holdings Inc.

3.050% Senior Note due 2061

Chubb INA Holdings Inc., a Delaware corporation (hereinafter called the “Company”, which term includes any successor corporation under the Indenture referred to below), for value received, hereby promises to pay to Cede & Co., or registered assigns, the principal sum of [    ] HUNDRED MILLION ([    ],000,000) on December 15, 2061 and to pay interest thereon from November 18, 2021 or from the most recent interest payment date to which interest has been paid or duly provided for, payable semi-annually on June 15 and December 15 in each year (each, an “Interest Payment Date”), commencing June 15, 2022, at the rate of 3.050% per annum, until the principal hereof (and any Additional Amounts (as defined below)) is paid or duly made available

1

for payment. Interest on this Note shall be computed on the basis of a 360-day year consisting of twelve 30-day months. If any Interest Payment Date or the maturity date falls on a day that is not a Business Day, the required payment shall be made on the next Business Day as if it were made on the date such payment was due and no interest shall accrue on the amount so payable for the period from and after such Interest Payment Date or the maturity date, as the case may be, to such next Business Day. The interest so payable and punctually paid or duly provided for on any Interest Payment Date will, as provided in the Indenture referred to herein, be paid to the Person in whose name this Note (or one or more Predecessor Securities) is registered at the close of business on the regular record date for such interest, which shall be June 1 or December 1 (whether or not a Business Day), as the case may be, next preceding such Interest Payment Date. Any such interest which is payable, but is not punctually paid or duly provided for, on any Interest Payment Date shall forthwith cease to be payable to the registered Holder hereof on the relevant regular record date by virtue of having been such Holder, and may be paid to the Person in whose name this Note (or one or more Predecessor Securities) is registered at the close of business on a subsequent Special Record Date (which shall be at least 10 days before the payment date) for the payment of such defaulted interest to be fixed by the Company, notice whereof shall be given to the Holders of Notes of this series not less than 10 days prior to such Special Record Date, or may be paid at any time in any other lawful manner not inconsistent with the requirements of any securities exchange on which the Notes may be listed, and upon such notice as may be required by such exchange, all as more fully provided in the Indenture referred to herein. Any interest paid on this Note shall be increased to the extent necessary to pay Additional Amounts as set forth in this Note.

Payment of the principal of, interest on or any Redemption Price or Additional Amounts in respect of this Note shall be made at the office or agency of the Company and the Guarantor (as defined below) maintained for that purpose in The Borough of Manhattan, The City of New York, in such coin or currency of the United States of America as at the time of payment is legal tender for payment of public and private debts; provided, however, that, at the option of the Company or the Guarantor, interest may be paid by check mailed to the address of the Person entitled thereto as such address shall appear in the Security Register; provided, further, that payment to DTC or any successor Depository may be made by wire transfer to the account designated by DTC or such successor depository in writing.

This Note is one of a duly authorized issuance of securities of the Company (herein called the “Notes”), fully and unconditionally guaranteed as to payment of principal premium, if any, and interest by Chubb Limited, a company limited by shares (Aktiengesellschaft) under the laws of Switzerland (the “Guarantor”), issued and to be issued in one or more series under an Indenture, dated as of August 1, 1999, as supplemented by the First Supplemental Indenture, dated as of March 13, 2013 (such Indenture and First Supplemental Indenture together herein called, together with all indentures supplemental thereto, the “Indenture”), among the Company (formerly known as ACE INA Holdings Inc.), the Guarantor (formerly known as ACE Limited) and The Bank of New York Mellon Trust Company, N.A. (as successor to J.P. Morgan Trust Company, National Association and The First National Bank of Chicago), as Trustee (herein called the “Trustee”, which term includes any successor trustee under the Indenture), to which the Indenture and all indentures supplemental thereto referenced is hereby made for a statement of the respective rights, limitations of rights, duties and immunities thereunder of the Company, the Guarantor, the Trustee and the Holders of the Notes, and of the terms upon which the Notes

2

are, and are to be, authenticated and delivered. This Note is one of the series designated on the face hereof, initially limited (subject to exceptions related to further Notes provided in the Indenture) to the aggregate principal amount specified in the Officer’s Certificate, dated as of November 18, 2021, establishing the terms of the Notes pursuant to the Indenture.

The Notes are senior unsecured obligations of the Company. The Company’s obligation to pay the principal of, interest on or any Additional Amounts in respect of the Notes is unconditionally guaranteed on a senior unsecured basis by the Guarantor pursuant to Article 16 of the Indenture.

If an Event of Default with respect to the Notes shall occur and be continuing, the principal of the Notes may be declared due and payable in the manner and with the effect provided in the Indenture.

The Indenture contains provisions permitting, with certain exceptions as therein provided, the amendment thereof and the modification of the rights and obligations of the Company or the Guarantor and the rights of the Holders of the Securities of each series issued under the Indenture at any time by the Company, the Guarantor and the Trustee with the written consent of the Holders of not less than a majority in aggregate principal amount of the Securities at the time Outstanding of each series affected thereby. The Indenture also contains provisions permitting the Holders of specified percentages in aggregate principal amount of the Securities of any series at the time Outstanding, on behalf of the Holders of all Securities of such series, to waive compliance by the Company or the Guarantor with certain provisions of the Indenture and certain past defaults under the Indenture and their consequences. Any such consent or waiver by the Holder of this Note shall be conclusive and binding upon such Holder and upon all future Holders of this Note and of any Notes issued upon the registration of transfer hereof or in exchange herefor or in lieu hereof, whether or not notation of such consent or waiver is made upon this Note.

This Note is not subject to any sinking fund.

No reference herein to the Indenture and no provision of this Note or of the Indenture shall alter or impair the obligation of the Company, which is absolute and unconditional, to pay the principal of, interest on or any Redemption Price or any Additional Amounts in respect of this Note, at the times, place and rate, and in the coin or currency, herein and in the Indenture prescribed.

As provided in the Indenture and subject to certain limitations set forth therein and in this Note, the transfer of this Note may be registered on the Security Register upon surrender of this Note for registration of transfer at the office or agency of the Company and the Guarantor maintained for that purpose in any place where the principal of, interest on or any Additional Amounts in respect of this Note are payable, duly endorsed by, or accompanied by a written instrument of transfer in form satisfactory to the Company and the Security Registrar duly executed by, the Holder hereof or by his attorney duly authorized in writing, and thereupon one or more new Notes of this series and of like tenor, of authorized denominations and for the same aggregate principal amount, shall be issued to the designated transferee or transferees.

3

The Notes are issuable only in registered form without coupons in the denominations specified in the Officer’s Certificate, dated as of November 18, 2021, establishing the terms of the Notes, all as more fully provided in the Indenture and such Officer’s Certificate. As provided in the Indenture and in such Officer’s Certificate, and subject to certain limitations set forth in the Indenture, such Officer’s Certificate and in this Note, the Notes are exchangeable for a like aggregate principal amount of Notes of this series in different authorized denominations, as requested by the Holders surrendering the same.

No service charge shall be made for any such registration of transfer or exchange, but the Company may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection therewith, other than in certain cases provided in the Indenture.

Prior to due presentment of this Note for registration of transfer, the Company, the Guarantor, the Trustee and any agent of the Company, the Guarantor or the Trustee may treat the Person in whose name this Note is registered as the owner hereof for all purposes, whether or not this Note be overdue, and neither the Company, the Guarantor, the Trustee nor any such agent shall be affected by notice to the contrary.

The Notes are redeemable in whole at any time or in part from time to time prior to June 15, 2061 (the “Par Call Date”), at the Company’s option, at a Redemption Price equal to the greater of (i) 100 percent of the principal amount of the Notes being redeemed and (ii) the sum of the present value of the remaining scheduled payments of principal and interest on the Notes being redeemed that would be due if the Notes to be redeemed matured on the Par Call Date (not including any portion of such payments of interest accrued as of the Redemption Date) discounted to the Redemption Date on a semi-annual basis (assuming a 360-day year consisting of twelve 30-day months) at a discount rate equal to the Treasury Rate plus 20 basis points, plus, in each case, accrued and unpaid interest on the principal amount being redeemed to but excluding, the Redemption Date.

In addition, at any time on or after the Par Call Date, the Notes are redeemable in whole at any time or in part from time to time, at the Company’s option, at a Redemption Price equal to 100 percent of the principal amount of the Notes being redeemed plus accrued and unpaid interest on the principal amount being redeemed to, but excluding, the Redemption Date.

Any redemption made at the option of the Company shall be conducted in accordance with Article 11 of the Indenture, provided that any reference in Section 11.4 of the Indenture to 30 days shall be deemed to be 15 days for the purposes of this Note. Notwithstanding anything to the contrary in the Indenture, if fewer than all of the Notes are to be redeemed and the Notes are global notes held by DTC or its nominee, the particular Notes or portions thereof selected for redemption from the Outstanding Notes not previously redeemed shall be selected by DTC in accordance with its standard procedures. If the Notes are not then global notes held by DTC or its nominee, the Trustee will select the particular Notes or portions of the Notes for redemption from the Outstanding Notes not previously called by such method as the Trustee deems appropriate.

4

“Business Day” means any day other than a Saturday, Sunday or other day on which banking institutions in the City of New York are authorized or obligated by law, regulation or executive order to close.

“Comparable Treasury Issue” means the United States Treasury security selected by an Independent Investment Banker as having a maturity comparable to the remaining term of the Notes to be redeemed (assuming for this purpose that the Notes matured on the Par Call Date) that would be utilized, at the time of selection and in accordance with customary financial practice, in pricing new issues of corporate debt securities of comparable maturity to the remaining term of the Notes.

“Comparable Treasury Price” means (1) the average of four Reference Treasury Dealer Quotations for such Redemption Date, after excluding the highest and lowest Reference Treasury Dealer Quotations, or (2) if the Independent Investment Banker obtains fewer than four such Reference Treasury Dealer Quotations, the average of all such quotations.

“Independent Investment Banker” means either BofA Securities, Inc., Morgan Stanley & Co. LLC or Wells Fargo Securities, LLC, and their respective successors, as may be appointed from time to time by the Company or, if none of such firms is willing or able to select the Comparable Treasury Issue, an independent investment banking institution of national standing appointed by the Company.

“Reference Treasury Dealer” means: (i) each of BofA Securities, Inc., Morgan Stanley & Co. LLC and Wells Fargo Securities LLC, and their respective successors; provided, however, that if any of the foregoing shall cease to be a primary U.S. Government securities dealer in New York City, (a “Primary Treasury Dealer”) the Company will substitute another Primary Treasury Dealer; and (ii) another Primary Treasury Dealer selected by the Company.

“Reference Treasury Dealer Quotations” means, with respect to each Reference Treasury Dealer and any Redemption Date, the average, as determined by the Independent Investment Banker, of the bid and asked prices for the Comparable Treasury Issue (expressed in each case as a percentage of its principal amount) quoted in writing to the Independent Investment Banker at 5:00 p.m., New York City time, on the third Business Day preceding such Redemption Date.

“Treasury Rate” means, with respect to any Redemption Date, the rate per year equal to: (1) the yield, under the heading which represents the average for the immediately preceding week, appearing in the most recently published statistical release designated “H.15” or any successor publication which is published weekly by the Board of Governors of the Federal Reserve System and which establishes yields on actively traded United States Treasury securities adjusted to constant maturity under the caption “Treasury Constant Maturities,” for the maturity corresponding to the Comparable Treasury Issue (if no maturity is within three months before or after the remaining term, yields for the two published maturities most closely corresponding to the Comparable Treasury Issue shall be determined and the Treasury Rate shall be interpolated or extrapolated from such yields on a straight line basis, rounding to the nearest month) or (2) if such release (or any successor release) is not published during the week preceding the calculation date or does not contain such yields, the rate per year equal to the semi-annual equivalent yield-to-maturity of the Comparable Treasury Issue, calculated using a price for the Comparable Treasury Issue (expressed as a percentage of its principal amount) equal to the Comparable Treasury Price for such Redemption Date. The Treasury Rate shall be calculated on the third Business Day preceding the Redemption Date.

5

The Company or, in the event that payments are required to be made by the Guarantor pursuant to its obligations under the Guarantee, the Guarantor will, subject to the exceptions and limitations set forth below, pay such additional amounts as are necessary in order that the net payment by the Company, the Guarantor or a Paying Agent of the principal of, and premium, if any, and interest on this Note to a Holder, after withholding or deduction for any future tax, assessment or other governmental charge imposed by the United States, Switzerland or any other jurisdiction in which the Company or the Guarantor or, in each case, any successor Person substituted in accordance with the Indenture may be organized or resident for tax purposes, as applicable, or any political subdivision thereof or therein having the power to tax (a “Taxing Jurisdiction”), will not be less than the amount provided in this Note to be then due and payable (“Additional Amounts”); provided, however, that the foregoing obligation to pay Additional Amounts shall not apply: (1) to any tax, assessment or other governmental charge that would not have been imposed but for the Holder (or the beneficial owner for whose benefit such Holder holds this Note), or a fiduciary, settlor, beneficiary, member or shareholder of the Holder if the Holder is an estate, trust, partnership or corporation, or a person holding a power over an estate or trust administered by a fiduciary Holder, being considered as: (a) being or having been engaged in a trade or business in the Taxing Jurisdiction or having or having had a permanent establishment in the Taxing Jurisdiction; (b) having a current or former connection with the Taxing Jurisdiction (other than a connection arising solely as a result of the ownership of the Notes or the receipt of any payment or the enforcement of any rights thereunder), including being or having been a citizen or resident of the Taxing Jurisdiction; (c) being or having been a personal holding company, a passive foreign investment company or a controlled foreign corporation for United States income tax purposes or a corporation that has accumulated earnings to avoid United States federal income tax; (d) being or having been a “10-percent shareholder” of the Company or the Guarantor as defined in section 871(h)(3) of the United States Internal Revenue Code of 1986, as amended (the “Code”), or any successor provision; or (e) being a bank receiving payments on an extension of credit made pursuant to a loan agreement entered into in the ordinary course of its trade or business; (2) to any Holder that is not the sole beneficial owner of the Notes, or a portion of the Notes, or that is a fiduciary, partnership or limited liability company, but only to the extent that a beneficial owner with respect to the Holder, a beneficiary or settlor with respect to the fiduciary, or a beneficial owner or member of the partnership or limited liability company would not have been entitled to the payment of an Additional Amount had the beneficiary, settlor, beneficial owner or member received directly its beneficial or distributive share of the payment; (3) to any tax, assessment or other governmental charge that would not have been imposed but for the failure of the Holder or any other person to comply with certification, identification or information reporting requirements concerning the nationality, residence, identity or connection with the Taxing Jurisdiction of the Holder or beneficial owner of the Notes, if compliance is required by statute, by regulation of the Taxing Jurisdiction or any taxing authority therein or by an applicable income tax treaty to which the Taxing Jurisdiction is a party as a precondition to exemption from such tax, assessment or other governmental charge; (4) to any tax, assessment or other governmental charge that is payable otherwise than by withholding by the Company, the Guarantor or a Paying Agent from the payment; (5) to any tax, assessment or other governmental charge that would not have been

6

imposed but for a change in law, regulation, or administrative or judicial interpretation that becomes effective more than 15 days after the payment becomes due or is duly provided for, whichever occurs later; (6) to any estate, inheritance, gift, sales, excise, transfer, wealth, capital gains or personal property tax or similar tax, assessment or other governmental charge; (7) to any tax, assessment or other governmental charge required to be withheld by any paying agent from any payment of principal of or interest on any Note, if such payment can be made without such withholding by at least one other paying agent; (8) to any tax, assessment or other governmental charge that would not have been imposed but for the presentation by the Holder of any Note, where presentation is required, for payment on a date more than 30 days after the date on which payment became due and payable or the date on which payment thereof is duly provided for, whichever occurs later; (9) to any tax, assessment or other governmental charge imposed under Sections 1471 through 1474 of the Code (or any amended or successor provisions), any current or future regulations or official interpretations thereof, any agreement entered into pursuant to Section 1471(b) of the Code, any intergovernmental agreement entered into in connection with the implementation of the foregoing and any fiscal or regulatory legislation, rules or practices adopted pursuant to any such intergovernmental agreement; or (10) in the case of any combination of items (1), (2), (3), (4), (5), (6), (7), (8) and (9).

The Company shall be entitled to redeem this Note, at its option, at any time as a whole but not in part, upon not less than 15 nor more than 60 days’ notice, at 100 percent of the principal amount thereof, plus accrued and unpaid interest (if any) to the Redemption Date (subject to the right of Holders of record on the relevant record date to receive interest due on the relevant Interest Payment Date), in the event that the Company or the Guarantor has become or would become obligated to pay, on the next date on which any amount would be payable with respect to this Note, any Additional Amounts as a result of: (1) a change in or an amendment to the laws (including any regulations promulgated thereunder) of a Taxing Jurisdiction, which change or amendment is announced after November 15, 2021; or (2) any change in or amendment to any official position regarding the application or interpretation of such laws or regulations, which change or amendment is announced after November 15, 2021, and, in each case, the Company or the Guarantor, as applicable, cannot avoid such obligation by taking reasonable measures available to it.

The Indenture contains provisions whereby (i) the Company and the Guarantor may be discharged from their obligations with respect to the Notes (subject to certain exceptions) or (ii) the Company and the Guarantor may be released from their obligations under specified covenants and agreements in the Indenture, in each case if the Company or the Guarantor irrevocably deposits with the Trustee money or Government Obligations, or a combination thereof, in an amount sufficient, without consideration of any reinvestment, to pay and discharge the entire indebtedness on all Notes of this series, and satisfies certain other conditions, all as more fully provided in the Indenture.

This Note shall be governed by and construed in accordance with the laws of the State of New York applicable to agreements and instruments made and to be performed wholly within such State.

All terms used in this Note without definition that are defined in the Indenture shall have the meanings assigned to them in the Indenture.

7

[Remainder of Page Intentionally Left Blank]

8

Unless the Certificate of Authentication hereon has been executed by or on behalf of the Trustee under the Indenture by the manual signature of one of its authorized officers, this Note shall not be entitled to any benefits 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: November 18, 2021

CERTIFICATE OF AUTHENTICATION

This is one of the Securities of the series designated therein referred to in the within-mentioned Indenture.

Dated: November 18, 2021

ABBREVIATIONS

The following abbreviations, when used in the inscription on the face of this instrument, shall be construed as though they were written out in full according to applicable laws or regulations:

Additional abbreviations may also be used though not in the above list.

FOR VALUE RECEIVED, the undersigned registered Holder hereby sell(s), assign(s) and transfer(s) unto

[PLEASE INSERT SOCIAL SECURITY OR OTHER IDENTIFYING NUMBER OF ASSIGNEE]

[PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS OF ASSIGNEE]

the within Note and all rights thereunder, hereby irrevocably constituting and appointing                                                                        to transfer said Note on the books of the Company with full power of substitution in the premises.

Dated:    _____________________

Signature: _____________________

Notice: The signature to this assignment must correspond with the name as it appears upon the face of the within Note in every particular, without alteration or enlargement or any change whatsoever.

Signature Guaranty:    __________________________________________________________

Signatures must be guaranteed by an “eligible guarantor institution” meeting the requirements of the Trustee, which requirements include membership or participation in the Security Transfer Agent Medallion Program (“STAMP”) or such other “signature guarantee program” as may be determined by the Trustee in addition to, or in substitution for, STAMP, all in accordance with the Securities Exchange Act of 1934, as amended.