BIP Brookfield Infrastructure Partners LP

Description of Class A Preferred Units

        The following description of the particular terms of the Class A Preferred Units supplements the description of the general terms and provisions of preferred units in the accompanying base prospectus and does not purport to be complete. The following description is subject to, and qualified in its entirety by reference to, the provisions of our Partnership Agreement, including the Third Amendment thereto ("Amendment No. 3"), which will be entered into in connection with the closing of this offering and will be filed as an exhibit to a report on Form 6-K. We urge you to read our Partnership Agreement, including Amendment No. 3, because it, and not this description, will define your rights as a holder of the Class A Preferred Units.

Series

        The Class A Preferred Units may be issued from time to time in one or more series. As of the date of this prospectus supplement, we have outstanding 4,989,265 Class A Preferred Limited Partnership Units, Series 1 (the "Series 1 Preferred Units") (which may be re-classified into Series 2 Preferred Units (as defined below)); 4,989,262 Class A Preferred Limited Partnership Units, Series 3 (the "Series 3 Preferred Units") (which may be re-classified into Class A Preferred Limited Partnership Units, Series 4 (the "Series 4 Preferred Units"); 9,986,588 Class A Preferred Limited Partnership Units, Series 5 (the "Series 5 Preferred Units") (which may be re-classified into Class A Preferred Limited Partnership Units, Series 6 (the "Series 6 Preferred Units"));

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11,979,750 Class A Preferred Limited Partnership Units, Series 7 (the "Series 7 Preferred Units") (which may be re-classified into Class A Preferred Limited Partnership Units, Series 8 (the "Series 8 Preferred Units")); 7,986,595 Class A Preferred Limited Partnership Units, Series 9 (the "Series 9 Preferred Units") (which may be re-classified into Class A Preferred Limited Partnership Units, Series 10 (the "Series 10 Preferred Units")); and 9,936,190 Class A Preferred Limited Partnership Units, Series 11 (the "Series 11 Preferred Units") (which may be re-classified into Class A Preferred Limited Partnership Units, Series 12 (the "Series 12 Preferred Units")) (collectively, the "Existing Preferred Units"). The BIP General Partner will fix the number of Class A Preferred Units in each additional series and the terms of each additional series before issue. The BIPC Guarantor is a guarantor of each series of the Existing Preferred Units as to the payment of distributions when due, the payment of amounts due upon redemption, and the payment of amounts due upon liquidation, dissolution or winding up of the Partnership.

        The Partnership's Series 1 Preferred Units, Series 3 Preferred Units, Series 5 Preferred Units, Series 7 Preferred Units, Series 9 Preferred Units and Series 11 Preferred Units are listed on the TSX under the symbols "BIP.PR.A", "BIP.PR.B", "BIP.PR.C", "BIP.PR.D", "BIP.PR.E" and "BIP.PR.F", respectively.

        The Series 1 Preferred Units were redeemable by the Partnership on June 30, 2020, and are redeemable by the Partnership on June 30 every five years thereafter, with the next redemption date on June 30, 2025 (each such redemption date, a "Series 1 Redemption Date"), for C$25.00 per Series 1 Preferred Unit, together with all accrued and unpaid distributions. Holders of the Series 1 Preferred Units will have the right, at their option, to reclassify their Series 1 Preferred Units into Series 2 Preferred Units, subject to certain conditions, on any Series 1 Redemption Date, with the next such date occuring on June 30, 2025. The Series 3 Preferred Units are redeemable by the Partnership on December 31, 2020 and on December 31 every five years thereafter for C$25.00 per Series 3 Preferred Unit, together with all accrued and unpaid distributions. Holders of the Series 3 Preferred Units will have the right, at their option, to reclassify their Series 3 Preferred Units into Series 4 Preferred Units, subject to certain conditions, on December 31, 2020 and on December 31 every five years thereafter. The Series 5 Preferred Units are redeemable by the Partnership on September 30, 2021 and on September 30 every five years thereafter for C$25.00 per Series 5 Preferred Unit, together with all accrued and unpaid distributions. Holders of the Series 5 Preferred Units will have the right, at their option, to reclassify their Series 5 Preferred Units into Series 6 Preferred Units, subject to certain conditions, on September 30, 2021 and on September 30 every five years thereafter. The Series 7 Preferred Units are redeemable by the Partnership on March 31, 2022 and on March 31 every five years thereafter for C$25.00 per Series 7 Preferred Unit, together with all accrued and unpaid distributions. Holders of the Series 7 Preferred Units will have the right, at their option, to reclassify their Series 7 Preferred Units into Series 8 Preferred Units, subject to certain conditions, March 31, 2022 and on March 31 every five years thereafter. The Series 9 Preferred Units are redeemable by the Partnership on March 31, 2023 and on March 31 every five years thereafter for C$25.00 per Series 9 Preferred Unit, together with all accrued and unpaid distributions. Holders of the Series 9 Preferred Units will have the right, at their option, to reclassify their Series 9 Preferred Units into Series 10 Preferred Units, subject to certain conditions, on March 31, 2023 and on March 31 every five years thereafter. The Series 11 Preferred Units are redeemable by the Partnership on December 31, 2023 and on December 31 every five years thereafter for C$25.00 per Series 11 Preferred Unit, together with all accrued and unpaid distributions. Holders of the Series 11 Preferred Units will have the right, at their option, to reclassify their Series 11 Preferred Units into Series 12 Preferred Units, subject to certain conditions, on December 31, 2023 and on December 31 every five years thereafter.

Priority

        The Class A Preferred Units rank senior to the LP Units with respect to priority in the payment of distributions and in the distribution of the assets in the event of the liquidation, dissolution or winding-up of the Partnership, whether voluntary or involuntary. Each series of Class A Preferred Units ranks on parity in right of payment with every other series of the Class A Preferred Units with respect to priority in the payment of distributions and in the distribution of the assets in the event of the liquidation, dissolution or winding-up of the Partnership, whether voluntary or involuntary; however, only the Existing Preferred Units will have the benefit of the guarantees from the BIPC Guarantor.

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Unitholder Approvals

        In addition to any other approvals required by law, the approval of all amendments to the rights, privileges, restrictions and conditions attaching to the Class A Preferred Units as a class and any other approval to be given by the holders of the Class A Preferred Units may be (i) given by a resolution signed by the holders of Class A Preferred Units owning not less than the percentage of the Class A Preferred Units that would be necessary to authorize such action at a meeting of the holders of the Class A Preferred Units at which all holders of the Class A Preferred Units were present and voted or were represented by proxy or (ii) passed by an affirmative vote of at least 66²/3% of the votes cast at a meeting of holders of the Class A Preferred Units duly called for that purpose and at which the holders of at least 25% of the outstanding Class A Preferred Units are present or represented by proxy or, if no quorum is present or represented by proxy at such meeting, at an adjourned meeting at which the holders of Class A Preferred Units then present would form the necessary quorum. At any meeting of holders of Class A Preferred Units as a class, each such holder shall be entitled to one vote in respect of each Class A Preferred Unit held.

        We may issue Junior Securities and Parity Securities (including additional Class A Preferred Units) from time to time without the consent of holders of outstanding Class A Preferred Units. In addition, unless we have received the affirmative vote or consent of the holders of at least a majority of the outstanding Class A Preferred Units, we may not issue any Senior Securities.

Description of Series 13 Preferred Units

        The following description of the particular terms of the Series 13 Preferred Units supplements the description of the general terms and provisions of Class A Preferred Units described above under "— Description of Class A Preferred Units" and in the accompanying base prospectus, and does not purport to be complete. The following description is subject to, and qualified in its entirety by reference to, the provisions of our Partnership Agreement, including Amendment No. 3 thereto, which will be entered into in connection with the closing of this offering and will be filed as an exhibit to a report on Form 6-K. We urge you to read our Partnership Agreement, including Amendment No. 3, because it, and not this description, will define your rights as a holder of the Series 13 Preferred Units.

General

        The Series 13 Preferred Units offered hereby are a new series of preferred units of the Partnership. Upon completion of this offering, there will be                        Series 13 Preferred Units issued and outstanding (assuming no exercise of the underwriters' option to purchase additional Series 13 Preferred Units). We may, without notice to or consent of the holders of the then-outstanding Series 13 Preferred Units, authorize and issue additional Junior Securities (as defined under "Summary — The Offering — Ranking") and, subject to the limitations described under "— Voting Rights," Senior Securities and Parity Securities (each, as defined under "Summary — The Offering — Ranking").

        The holders of our LP Units, Existing Preferred Units, Series 13 Preferred Units and other partnership securities are entitled to receive, to the extent permitted by law and as provided in our Partnership Agreement, such distributions as may from time to time be declared by the BIP General Partner. Upon any liquidation, dissolution or winding-up of our affairs, whether voluntary or involuntary, the holders of our LP Units, Existing Preferred Units, Series 13 Preferred Units, general partner interest and other partnership securities (if any) are entitled to receive distributions of our assets as provided in our Partnership Agreement, after we have satisfied or made provision for our outstanding indebtedness and other obligations and after payment to the holders of any class or series of limited partner interests having preferential rights to receive distributions of our assets over each such class of limited partner interests.

        When issued and paid for in the manner described in this prospectus supplement and the accompanying base prospectus, the Series 13 Preferred Units offered hereby will be fully paid and nonassessable. Subject to the matters described under "— Liquidation Rights," each Series 13 Preferred Unit will generally have a fixed liquidation preference of $25.00 per Series 13 Preferred Unit (subject to adjustment for any splits, combinations or similar adjustment to the Series 13 Preferred Units) plus an amount equal to accrued and unpaid distributions thereon to, but excluding, the date fixed for payment, whether or not declared.

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        Unlike our indebtedness, the Series 13 Preferred Units will represent perpetual interests in us and will not give rise to a claim for payment of a principal amount at a particular date. As such, the Series 13 Preferred Units will rank junior to all of our current and future indebtedness with respect to assets available to satisfy claims against us. The rights of the holders of Series 13 Preferred Units to receive the liquidation preference will be subject to the rights of the holders of any Senior Securities and the proportional rights of holders of Parity Securities (including the Existing Preferred Units).

        All of the Series 13 Preferred Units offered hereby will be represented by one or more certificates issued to DTC (and its successors or assigns or any other securities depositary selected by us) (the "Securities Depositary") and registered in the name of its nominee, for credit to an account of a direct or indirect participant in the Securities Depositary. So long as a Securities Depositary has been appointed and is serving, no person acquiring Series 13 Preferred Units will be entitled to receive a certificate representing such Series 13 Preferred Units unless applicable law otherwise requires or the Securities Depositary resigns or is no longer eligible to act as such and a successor is not appointed. See "— Book-Entry System."

        The Series 13 Preferred Units will not be convertible into LP Units or any other securities and will not have exchange rights or be entitled or subject to any preemptive or similar rights, except under circumstances set forth under "— Substitution or Variation" below. The Series 13 Preferred Units will not be entitled or subject to mandatory redemption or to any sinking fund requirements. The Series 13 Preferred Units will be subject to redemption, in whole or in part, as applicable, at our option (i) following a Change in Tax Law, (ii) commencing on October 15, 2025, at our option, or (iii) prior to October 15, 2025 upon occurrence of a Ratings Event. See "— Redemption."

        We have appointed Computershare Inc. as the paying agent (the "Paying Agent"), and the registrar and transfer agent (the "Registrar and Transfer Agent"), for the Series 13 Preferred Units with its at its principal office in 150 Royall Street, Canton MA 02021.

Ranking

        The Series 13 Preferred Units will, with respect to anticipated quarterly distributions and distributions upon the liquidation, winding-up and dissolution of our affairs, rank:

•

senior to the Junior Securities;



•

on parity in right of payment with the Parity Securities (including the Existing Preferred Units);



•

junior to any Senior Securities; and



•

junior to all of our existing and future indebtedness with respect to assets available to satisfy claims against us.

        In addition, the Series 13 Preferred Units will be structurally subordinated to all existing and future debt and guarantee obligations of our subsidiaries and any capital stock of our subsidiaries (including the BIPC Guarantees of the Existing Preferred Units) held by others as to the payment of distributions and amounts payable upon a liquidation event. The Series 13 Preferred Units have not been, and will not be, guaranteed by any of our subsidiaries and will not be guaranteed by the BIPC Guarantor that guarantees the Existing Preferred Units.

        Under our Partnership Agreement, we may issue Junior Securities and Parity Securities (including additional Class A Preferred Units) from time to time in one or more series without the consent of the holders of the Series 13 Preferred Units. The BIP General Partner has the authority to determine the designations, preferences, rights, powers, guarantees and duties of any such series before the issuance of any units of that series. The BIP General Partner will also determine the number of units constituting each series of securities. Our ability to issue additional Parity Securities in certain circumstances or Senior Securities is limited as described under "— Voting Rights." Parity Securities with respect to the Series 13 Preferred Units may include classes and series of the Partnership's securities (including other series of Class A Preferred Units, such as the Existing Preferred Units) that have different coupons, distribution rates, mechanics, payment periods, payment dates, record dates and/or other terms than the Series 13 Preferred Units.

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Liquidation Rights

        In the event of the liquidation, dissolution or winding-up of the Partnership, unless the Partnership is continued under the election to reconstitute and continue the Partnership, the holders of the Series 13 Preferred Units will be entitled to receive $25.00 per unit, together with all accrued (whether or not declared) and unpaid distributions up to but excluding the date of payment or distribution, before any amount is paid or any assets of the Partnership are distributed to the holders of any units of the Partnership ranking junior to the Series 13 Preferred Units. Upon payment of such amounts, the holders of the Series 13 Preferred Units will not be entitled to share in any further distribution of the assets of the Partnership. The rights of the holders of Series 13 Preferred Units to receive the liquidation preference will be subject to the rights of the holders of any Senior Securities and the proportional rights of holders of Parity Securities (including the Existing Preferred Units which benefit from the BIPC Guarantee from the BIPC Guarantor as well as any future Class A Preferred Units that may benefit from a similar guarantee).

Voting Rights

        Holders of Series 13 Preferred Units are not entitled to receive notice of, attend, or vote at, any meeting of unitholders of the Partnership, unless and until the Partnership shall have failed to pay eight quarterly distributions on the Series 13 Preferred Units, whether or not consecutive and whether or not such distributions have been declared and whether or not there are any monies of the Partnership legally available for distributions under Bermuda law. In the event of such non-payment, and for only so long as any such distributions remain in arrears, the holders of Series 13 Preferred Units will be entitled to receive notice of and to attend each meeting of unitholders of the Partnership (other than any meetings at which only holders of another specified class or series are entitled to vote) and shall have the right, at any such meeting, to one vote for each Series 13 Preferred Unit held. No other voting rights shall attach to the Series 13 Preferred Units in any circumstances. Upon payment of the entire amount of all distributions on the Series 13 Preferred Units in arrears, the voting rights of the holders thereof shall forthwith cease (unless and until the same default shall again arise as described herein).

        Except as set forth in our Partnership Agreement or as otherwise required by Bermuda law, and except as described in the paragraph above, the Series 13 Preferred Units will have no voting rights. In addition, we may not adopt an amendment to our Partnership Agreement that has a material adverse effect on the powers, preferences, duties or special rights of the Series 13 Preferred Units unless such amendment (i) is approved by a resolution signed by the holders of Series 13 Preferred Units owning not less than the percentage of the Series 13 Preferred Units that would be necessary to authorize such action at a meeting of the holders of the Series 13 Preferred Units at which all holders of the Series 13 Preferred Units were present and voted or were represented by proxy or (ii) is passed by an affirmative vote of at least 66²/3% of the votes cast at a meeting of holders of the Series 13 Preferred Units duly called for that purpose and at which the holders of at least 25% of the outstanding Series 13 Preferred Units are present or represented by proxy or, if no quorum is present at such meeting, at an adjourned meeting at which the holders of Series 13 Preferred Units then present would form the necessary quorum. For the avoidance of doubt, for purposes of this voting requirement, any amendment to our Partnership Agreement (i) relating to the issuance of additional limited partner interests (subject to the voting rights regarding the issuance of Senior Securities discussed in "— Description of Class A Preferred Units — Unitholder Approvals" above) or (ii) in connection with a merger or another transaction in which we are the surviving entity and the Series 13 Preferred Units remain outstanding with the terms thereof materially unchanged in any respect adverse to the holders of Series 13 Preferred Units, will be deemed to not materially adversely affect the terms of the Series 13 Preferred Units.

        On any matter on which the holders of the Series 13 Preferred Units are entitled to vote as a class, such holders will be entitled to one vote per Series 13 Preferred Unit. The Series 13 Preferred Units held by us or any of our subsidiaries or controlled affiliates will not be entitled to vote.

        Series 13 Preferred Units held in nominee or street name account will be voted by the broker or other nominee in accordance with the instruction of the beneficial owner unless the arrangement between the beneficial owner and its nominee provides otherwise.

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Distributions

General

        Holders of Series 13 Preferred Units will be entitled to receive, as and when declared by the board of directors of the BIP General Partner out of legally available funds for such purpose, cumulative quarterly cash distributions. Unless otherwise determined by the BIP General Partner, distributions on the Series 13 Preferred Units will be deemed to have been paid out of our available cash with respect to the quarter ended immediately preceding the quarter in which the distribution is made.

        Distributions on Series 13 Preferred Units will be cumulative from the date of original issue and will be payable quarterly in arrears (as described under "— Distribution Payment Dates") commencing on December 15, 2020, when, as, and if declared by the BIP General Partner out of legally available funds for such purpose. A pro-rated initial distribution on the Series 13 Preferred Units will be paid on December 15, 2020 in an amount equal to approximately $                                     per unit.

        The distribution rate for the Series 13 Preferred Units will be                        % per annum of the $25.00 liquidation preference per unit (equal to $                                    per unit per annum).

Distribution Payment Dates

        The "Distribution Payment Dates" for the Series 13 Preferred Units will be the fifteenth day of March, June, September and December in each year, commencing on December 15, 2020. Distributions will accrue in each such period from and including the preceding Distribution Payment Date or the initial issue date, as the case may be, to but excluding the applicable Distribution Payment Date for such period, and distributions will accrue on accrued distributions at the applicable distribution rate. If any Distribution Payment Date otherwise would fall on a day that is not a Business Day, declared distributions will be paid on the immediately succeeding Business Day without the accrual of additional distributions. Distributions on the Series 13 Preferred Units will be payable based on a 360-day year consisting of twelve 30-day months. "Business Day" means every day except a Saturday or Sunday, or a day which is a statutory or civic holiday in Bermuda, the Province of Ontario, or the State of New York.

Payment of Distributions

        Not later than 5:00 p.m., New York City time, on each Distribution Payment Date, we will pay quarterly distributions, if any, on the Series 13 Preferred Units that have been declared by the BIP General Partner to the holders of such Series 13 Preferred Units as such holders' names appear on our unit transfer books maintained by the Registrar and Transfer Agent on the applicable record date. The record date for each distribution on our Series 13 Preferred Units will be the last business day of the calendar month prior to the applicable Distribution Payment Date, or such other record date as may be fixed by the BIP General Partner.

        So long as the Series 13 Preferred Units are held of record by the nominee of the Securities Depositary, declared distributions will be paid to the Securities Depositary in same-day funds on each Distribution Payment Date. The Securities Depositary will credit accounts of its participants in accordance with the Securities Depositary's normal procedures. The participants will be responsible for holding or disbursing such payments to beneficial owners of the Series 13 Preferred Units in accordance with the instructions of such beneficial owners.

        No distribution may be declared or paid or set apart for payment on any Junior Securities (other than a distribution payable solely in Junior Securities) unless all accrued and unpaid distributions up to and including the distribution payable for the last completed period for which distributions were payable on all outstanding Series 13 Preferred Units and any Parity Securities (including the Existing Preferred Units) have been declared and paid or set apart for payment. Accrued distributions in arrears for any past distribution period may be declared by the BIP General Partner and paid on any date fixed by the BIP General Partner, whether or not a Distribution Payment Date, to holders of the Series 13 Preferred Units on the record date for such payment, which may not be less than 10 days before such distribution payment dates. To the extent a distribution period applicable to a class of Junior Securities or Parity Securities is shorter than the distribution period applicable to the Series 13 Preferred Units (e.g., monthly rather than quarterly), the BIP General Partner may declare and pay regular distributions with respect to such Junior Securities or Parity Securities so long as, at the time of

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declaration of such distribution, (i) there are no Series 13 Preferred Unit distribution payments in arrears and (ii) the BIP General Partner expects to have sufficient funds to pay the full distribution in respect of the Series 13 Preferred Units on the next successive Distribution Payment Date.

        Subject to the next succeeding sentence, if all accrued distributions in arrears on all outstanding Series 13 Preferred Units and any Parity Securities (including the Existing Preferred Units) have not been declared and paid, or sufficient funds for the payment thereof have not been set apart, payment of accrued distributions in arrears will be made in order of their respective distribution payment dates, commencing with the earliest distribution payment date. If less than all distributions payable with respect to all Series 13 Preferred Units and any Parity Securities (including the Existing Preferred Units) are paid, any partial payment will be made pro rata with respect to the Series 13 Preferred Units and any Parity Securities (including the Existing Preferred Units) entitled to a distribution payment at such time in proportion to the aggregate amounts remaining due in respect of such Series 13 Preferred Units and Parity Securities (including the Existing Preferred Units) at such time.

        Holders of the Series 13 Preferred Units will not be entitled to any distribution, whether payable in cash, property or units of the Partnership, in excess of full cumulative distributions. Except insofar as distributions accrue on the amount of any accrued and unpaid distributions no interest or sum of money in lieu of interest will be payable in respect of any distribution payment which may be in arrears on the Series 13 Preferred Units.

Payment of Additional Amounts

        We will make all payments on the Series 13 Preferred Units free and clear of and without withholding or deduction at source for, or on account of, any present or future taxes, fees, duties, assessments or governmental charges of whatever nature imposed or levied by or on behalf of any Relevant Taxing Jurisdiction (as defined under "— Redemption — Optional Redemption Upon a Change in Tax Law"), unless such taxes, fees, duties, assessments or governmental charges are required to be withheld or deducted by (i) the laws (or any regulations or rulings promulgated thereunder) of any Relevant Taxing Jurisdiction or (ii) an official position regarding the application, administration, interpretation or enforcement of any such laws, regulations or rulings (including, without limitation, a holding by a court of competent jurisdiction or by a taxing authority in any Relevant Taxing Jurisdiction). If a withholding or deduction at source is required, we will, subject to certain limitations and exceptions described below, pay to the holders of the Series 13 Preferred Units such additional amounts as distributions as may be necessary so that every net payment made to such holders, after such withholding or deduction (including any such withholding or deduction from such additional amounts), will be equal to the amounts we would otherwise have been required to pay had no such withholding or deduction been required.

        We will not be required to pay any additional amounts for or on account of:

(a)

any tax, fee, duty, assessment or governmental charge of whatever nature that would not have been imposed but for the fact that such holder was a resident, domiciliary or national of, or engaged in business or maintained a permanent establishment or was physically present in, the Relevant Taxing Jurisdiction or any political subdivision thereof or otherwise had some connection with the Relevant Taxing Jurisdiction other than by reason of the mere ownership of, or receipt of payment under, the Series 13 Preferred Units or any Series 13 Preferred Units presented for payment (where presentation is required for payment) more than 30 days after the Relevant Date (except to the extent that the holder would have been entitled to such amounts if it had presented such shares for payment on any day within such 30 day period). The "Relevant Date" means, in respect of any payment, the date on which such payment first becomes due and payable, but if the full amount of the moneys payable has not been received by the distribution disbursing agent on or prior to such due date, it means the first date on which the full amount of such moneys having been so received and being available for payment to holders and notice to that effect shall have been duly given to the holders of the Series 13 Preferred Units;



(b)

any estate, inheritance, gift, sale, transfer, personal property or similar tax, assessment or other governmental charge or any tax, assessment or other governmental charge that is payable otherwise than by withholding or deduction from payment of the liquidation preference or of any distributions on the Series 13 Preferred Units;

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(c)

any tax, fee, duty, assessment or other governmental charge that is imposed or withheld by reason of the failure by the holder of such Series 13 Preferred Units to comply with any reasonable request by us addressed to the holder within 90 days of such request (i) to provide information concerning the nationality, residence or identity of the holder or (ii) to make any declaration or other similar claim or satisfy any information or reporting requirement that is required or imposed by statute, treaty, regulation or administrative practice of the Relevant Taxing Jurisdiction as a precondition to exemption from all or part of such tax, fee, duty, assessment or other governmental charge;



(d)

any tax, fee, duty, assessment or governmental charge imposed under the United States Internal Revenue Code of 1986, as amended; or



(e)

any combination of items (a), (b), (c) and (d).

        In addition, we will not pay additional amounts with respect to any payment on the Series 13 Preferred Units to any holder that is a fiduciary, partnership, limited liability company or other pass-through entity other than the sole beneficial owner of such Series 13 Preferred Units if such payment would be required by the laws of the Relevant Taxing Jurisdiction to be included in the income for tax purposes of a beneficiary or partner or settlor with respect to such fiduciary or a member of such partnership, limited liability company or other pass-through entity or a beneficial owner to the extent such beneficiary, partner or settlor would not have been entitled to such additional amounts had it been the holder of the Series 13 Preferred Units.

        If there is a substantial probability that we or any entity formed by a consolidation, merger or amalgamation (or similar transaction) involving us or the entity to which we convey, transfer or lease substantially all of our properties and assets (a "Successor Entity") would become obligated to pay any additional amounts as a result of a Change in Tax Law, we will also have the option to redeem the Series 13 Preferred Units as described in "— Redemption — Optional Redemption Upon a Change in Tax Law".

Redemption

Optional Redemption Upon a Ratings Event

        Prior to October 15, 2025, at any time within 120 days after the conclusion of any review or appeal process instituted by us following the occurrence of a Ratings Event (as defined below), we may, at our option, redeem the Series 13 Preferred Units in whole, but not in part, at a redemption price in cash per Series 13 Preferred Unit equal to $25.50 (102% of the liquidation preference of $25.00) plus an amount equal to all accrued and unpaid distributions thereon to, but excluding, the date fixed for redemption, whether or not declared. Any such redemption would be effected only out of funds legally available for such purpose and would be subject to compliance with the provisions of the instruments governing our outstanding indebtedness.

        "Ratings Event" means a change by any rating agency to the current criteria, which change results in (i) any shortening of the length of time for which the current criteria are scheduled to be in effect with respect to the Series 13 Preferred Units, or (ii) a lower Equity Credit being given to the Series 13 Preferred Units than the Equity Credit that would have been assigned to the Series 13 Preferred Units by such rating agency pursuant to the current criteria.

        "Equity Credit" for the purposes of the Series 13 Preferred Units means the dollar amount or percentage in relation to the stated liquidation preference amount of $25.00 per Series 13 Preferred Unit assigned to the Series 13 Preferred Units as equity, rather than debt, by a rating agency in evaluating the capital structure of an entity.

Optional Redemption Upon a Change in Tax Law

        We will have the option to redeem the Series 13 Preferred Units, in whole but not in part, at a redemption price of $25.00 per Series 13 Preferred Unit, if as a result of a Change in Tax Law there is, in our reasonable determination, a substantial probability that we or any Successor Entity would become obligated to pay any additional amounts on the next succeeding distribution payment date with respect to the Series 13 Preferred Units and the payment of those additional amounts cannot be avoided by the use of any reasonable measures available to us or any Successor Entity. We must provide not less than 30 days' and not more than 60 days'

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written notice of any such redemption. Any such redemption would be effected only out of funds legally available for such purpose and will be subject to compliance with the provisions of our outstanding indebtedness.

"Change in Tax Law" means (i) a change in or amendment to laws, regulations or rulings of any Relevant Taxing Jurisdiction, (ii) a change in the official application or interpretation of those laws, regulations or rulings, (iii) any execution of or amendment to any treaty affecting taxation to which any Relevant Taxing Jurisdiction is party or (iv) a decision rendered by a court of competent jurisdiction in any Relevant Taxing Jurisdiction, whether or not such decision was rendered with respect to us, in each case described in (i)-(iv) above occuring after the date of this prospectus supplement; provided that in the case of a Relevant Taxing Jurisdiction other than Bermuda in which a successor company is organized, such Change in Tax Law must occur after the date on which we consolidate, merge or amalgamate (or engage in a similar transaction) with the Successor Entity, or convey, transfer or lease substantially all of our properties and assets to the Successor Entity, as applicable.

"Relevant Taxing Jurisdiction" means (i) Bermuda or any political subdivision or governmental authority of or in Bermuda with the power to tax, (ii) any jurisdiction from or through which we or our distribution disbursing agent are making payments on the Series 13 Preferred Units or any political subdivision or governmental authority of or in that jurisdiction with the power to tax or (iii) any other jurisdiction in which BIP or a Successor Entity is organized or generally subject to taxation or any political subdivision or governmental authority of or in that jurisdiction with the power to tax.

Optional Redemption on or after October 15, 2025

        Any time on or after October 15, 2025, we may redeem, at our option, in whole or in part, the Series 13 Preferred Units at a redemption price in cash equal to $25.00 per Series 13 Preferred Unit plus an amount equal to all accrued and unpaid distributions thereon to, but excluding, the date of redemption, whether or not declared. We may undertake multiple partial redemptions. Any such redemption would be effected only out of funds legally available for such purpose and would be subject to compliance with the provisions of the instruments governing our outstanding indebtedness.

Redemption Procedures

        Any optional redemption shall be effected only out of funds legally available for such purpose. We will give notice of any redemption not less than 30 days and not more than 60 days before the scheduled date of redemption, to the holders of any Series 13 Preferred Units to be redeemed as such holders' names appear on our unit transfer books maintained by the Registrar and Transfer Agent at the address of such holders shown therein. Such notice shall state: (i) the redemption date, (ii) the number of Series 13 Preferred Units to be redeemed and, if less than all outstanding Series 13 Preferred Units are to be redeemed, the number (and, in the case of Series 13 Preferred Units in certificated form, the identification) of Series 13 Preferred Units to be redeemed from such holder, (iii) the redemption price, (iv) the place where any Series 13 Preferred Units in certificated form are to be redeemed and shall be presented and surrendered for payment of the redemption price therefor (which shall occur automatically if the certificate representing such Series 13 Preferred Units is issued in the name of the Securities Depositary or its nominee), and (v) that distributions on the Series 13 Preferred Units to be redeemed will cease to accrue from and after such redemption date.

        If less than all of the outstanding Series 13 Preferred Units are to be redeemed, the Series 13 Preferred Units to be redeemed will be determined on a pro rata basis disregarding fractions, or in such other manner as the BIP General Partner in its sole discretion may, by resolution, determine. So long as all Series 13 Preferred Units are held of record by the nominee of the Securities Depositary, we will give notice, or cause notice to be given, to the Securities Depositary of the number of Series 13 Preferred Units to be redeemed. Thereafter, each participant will select the number of Series 13 Preferred Units to be redeemed from each beneficial owner for whom it acts (including the participant, to the extent it holds Series 13 Preferred Units for its own account). A participant may determine to redeem Series 13 Preferred Units from some beneficial owners (including the participant itself) without redeeming Series 13 Preferred Units from the accounts of other beneficial owners. Any Series 13 Preferred Units not redeemed will remain outstanding and entitled to all the rights and preferences of Series 13 Preferred Units under our Partnership Agreement.

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        So long as the Series 13 Preferred Units are held of record by the nominee of the Securities Depositary, the redemption price will be paid by the Paying Agent to the Securities Depositary on the redemption date. The Securities Depositary's normal procedures provide for it to distribute the amount of the redemption price in same-day funds to its participants who, in turn, are expected to distribute such funds to the persons for whom they are acting as agent.

        If we give or cause to be given a notice of redemption, then we will deposit with the Paying Agent funds sufficient to redeem the Series 13 Preferred Units as to which notice has been given by 10:00 a.m., New York City time, on the date fixed for redemption, and will give the Paying Agent irrevocable instructions and authority to pay the redemption price to the holder or holders thereof upon surrender or deemed surrender (which will occur automatically if the certificate representing such Series 13 Preferred Units is issued in the name of the Securities Depositary or its nominee) of the certificates therefor. If a notice of redemption shall have been given, then from and after the date fixed for redemption, unless we default in providing funds sufficient for such redemption at the time and place specified for payment pursuant to the notice, all distributions on such Series 13 Preferred Units will cease to accrue and all rights of holders of such Series 13 Preferred Units as limited partners will cease (and such Series 13 Preferred Units shall not thereafter be transferred on the books of the Registrar and Transfer Agent or be deemed outstanding for any purpose whatsoever), except the right to receive the redemption price, including an amount equal to accrued and unpaid distributions to the date fixed for redemption, whether or not declared. The holders of Series 13 Preferred Units will have no claim to the interest income, if any, earned on such funds deposited with the Paying Agent. Any funds deposited with the Paying Agent hereunder by us for any reason, including, but not limited to, redemption of Series 13 Preferred Units, that remain unclaimed or unpaid after one year after the applicable redemption date or other payment date, shall be, to the extent permitted by law, repaid to us upon our written request, after which repayment the holders of the Series 13 Preferred Units entitled to such redemption or other payment shall have recourse only to us.

        If only a portion of the Series 13 Preferred Units represented by a certificate has been called for redemption, upon surrender of the certificate to the Paying Agent (which will occur automatically if the certificate representing such Series 13 Preferred Units is registered in the name of the Securities Depositary or its nominee), we will issue and the Paying Agent will deliver to the holder of such Series 13 Preferred Units a new certificate (or adjust the applicable book-entry account) representing the number of Series 13 Preferred Units represented by the surrendered certificate that have not been called for redemption.

        Notwithstanding any notice of redemption, there will be no redemption of any Series 13 Preferred Units called for redemption until funds sufficient to pay the full redemption price of such Series 13 Preferred Units, including all accrued and unpaid distributions to, but excluding, the date of redemption, whether or not declared, have been deposited by us with the Paying Agent.

        We may from time to time purchase Series 13 Preferred Units, including by tender offer, open market purchases, negotiated transactions or otherwise, subject to compliance with all applicable securities and other laws. We have no obligation, or any present plan or intention, to purchase any Series 13 Preferred Units. Any Series 13 Preferred Units that we redeem or otherwise acquire will be cancelled.

        Notwithstanding the foregoing, unless all accrued and unpaid distributions up to and including the distribution payable for the last completed period for which distributions were payable on all Series 13 Preferred Units and any Parity Securities (including the Existing Preferred Units) have been declared and paid or set apart for payment, we may not repurchase, redeem or otherwise acquire, in whole or in part, any Series 13 Preferred Units or Parity Securities (including the Existing Preferred Units) except pursuant to a purchase or exchange offer made on the same relative terms to all holders of Series 13 Preferred Units and any Parity Securities (including the Existing Preferred Units). As long as any Series 13 Preferred Units are outstanding, except out of the net cash proceeds of a substantially concurrent issue of Junior Securities, we may not redeem, repurchase or otherwise acquire any partnership interests in the Partnership (other than a Class A Preferred Unit) or any other series of Junior Securities unless all accrued and unpaid distributions up to and including the distribution payable for the last completed period for which distributions were payable on all Series 13 Preferred Units and any Parity Securities (including the Existing Preferred Units) have been declared and paid or set apart for payment.

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Substitution or Variation

        At any time following a Tax Event, we may, without the consent of any holders of the Series 13 Preferred Units, vary the terms of the Series 13 Preferred Units such that they remain securities, or exchange the Series 13 Preferred Units with new securities, which would eliminate the substantial probability that we or any Successor Entity would be required to pay any additional amounts with respect to the Series 13 Preferred Units as a result of a Change in Tax Law. The terms of the varied securities or new securities considered in the aggregate cannot be less favorable to holders than the terms of the Series 13 Preferred Units prior to being varied or exchanged; provided that no such variation of terms or securities received in exchange shall change the specified denominations of, distribution payable on, the redemption dates (other than any extension of the period during which an optional redemption may not be exercised by us) or currency of the Series 13 Preferred Units, reduce the liquidation preference thereof, lower the ranking in right of payment with respect to the payment of distributions or the distribution of assets upon liquidation, dissolution or winding-up of the Series 13 Preferred Units, or change the foregoing list of items that may not be so amended as part of such variation or exchange. Further, no such variation of terms or securities received in exchange shall impair the right of a holder of the securities to institute suit for the payment of any amounts due, but unpaid with respect to such holder's securities.

        Prior to any variation or exchange, we will be required to receive an opinion of independent legal advisers to the effect that holders and beneficial owners of the Series 13 Preferred Units (including as holders and beneficial owners of the varied or exchanged securities) will not recognize income, gain or loss for U.S. federal income tax purposes as a result of such variation or exchange and will be subject to U.S. federal income tax on the same amounts, in the same manner and at the same times as would have been the case had such variation or exchange not occurred.

No Sinking Fund

        The Series 13 Preferred Units will not have the benefit of any sinking fund.

Limited Duties

        The Bermuda Limited Partnership Act 1883, as amended, under which the Partnership has been established, does not impose statutory fiduciary duties on a general partner of a limited partnership in the same manner that certain corporate statutes, such as the Delaware Revised Uniform Limited Partnership Act, impose fiduciary duties on directors of a corporation. In general, under applicable Bermudian legislation, a general partner has a duty to act in good faith and subject to any express provisions of the partnership agreement to the contrary, to act in the interests of the limited partnership. A general partner also has certain limited duties to its limited partners, such as the duty to render accounts, account for private profits and not compete with the partnership in business. In addition, Bermudian common law recognizes that a general partner owes a duty of utmost good faith to its limited partners. However, to the extent that the BIP General Partner owes any such fiduciary duties to the Partnership and holders of partnership interests in the Partnership, these duties have been modified pursuant to our Partnership Agreement as a matter of contract law, with the exception of the duty of the BIP General Partner to act in good faith, which cannot be modified.

Book-Entry System

        All Series 13 Preferred Units offered hereby will be represented by one or more certificates issued to the Securities Depositary, and registered in the name of its nominee (initially, Cede & Co.), for credit to an account of a direct or indirect participant in the Securities Depositary. The Series 13 Preferred Units offered hereby will continue to be represented by one or more certificates registered in the name of the Securities Depositary or its nominee, and no holder of the Series 13 Preferred Units offered hereby will be entitled to receive a certificate evidencing such Series 13 Preferred Units unless otherwise required by law or the Securities Depositary gives notice of its intention to resign or is no longer eligible to act as such and we have not selected a substitute Securities Depositary within 60 calendar days thereafter. Payments and communications made by us to holders of the Series 13 Preferred Units will be duly made by making payments to, and communicating with, the Securities Depositary. Accordingly, unless certificates are available to holders of the Series 13 Preferred Units,

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each purchaser of Series 13 Preferred Units must rely on (i) the procedures of the Securities Depositary and its participants to receive distributions, any redemption price, liquidation preference and notices, and to direct the exercise of any voting rights, with respect to such Series 13 Preferred Units and (ii) the records of the Securities Depositary and its participants to evidence its ownership of such Series 13 Preferred Units.

        So long as the Securities Depositary (or its nominee) is the sole holder of the Series 13 Preferred Units, no beneficial holder of the Series 13 Preferred Units will be deemed to be a holder of Series 13 Preferred Units. DTC, the initial Securities Depositary, is a New York-chartered limited purpose trust company that performs services for its participants, some of whom (and/or their representatives) own DTC. The Securities Depositary maintains lists of its participants and will maintain the positions (i.e., ownership interests) held by its participants in the Series 13 Preferred Units, whether as a holder of the Series 13 Preferred Units for its own account or as a nominee for another holder of the Series 13 Preferred Units.

Series 13 Holding LP Mirror Units

        On the closing of this offering, the Holding LP Partnership Agreement will be amended to authorize and create a proportionate number of preferred units in the capital of the Holding LP with terms designed to mirror the economic terms of the Series 13 Preferred Units (the "Series 13 Holding LP Mirror Units"), and we will use the proceeds of this offering to subscribe for such Series 13 Holding LP Mirror Units. The Holding LP Partnership Agreement will be amended by the Partnership, in our capacity as managing general partner of the Holding LP, pursuant to Section 18.1 of the Holding LP Partnership Agreement.

        The terms of the Series 13 Holding LP Mirror Units will provide that no distribution may be declared or paid or set apart for payment on any Mirror Junior Securities (as defined below) (other than a distribution payable solely in Mirror Junior Securities) unless full cumulative distributions have been or contemporaneously are being paid or provided for on all outstanding Series 13 Holding LP Mirror Units and any Mirror Parity Securities (as defined below) through the most recent respective distribution payment dates. To the extent a distribution period applicable to a class of Mirror Junior Securities or Mirror Parity Securities is shorter than the distribution period applicable to the Series 13 Holding LP Mirror Units (e.g., monthly rather than quarterly), we may declare and pay regular distributions with respect to such Mirror Junior Securities or Mirror Parity Securities so long as, at the time of declaration of such distribution, we expect to have sufficient funds to pay the full distribution in respect of the Series 13 Holding LP Mirror Units on the next successive distribution payment date.

        "Mirror Junior Securities" means the Redemption-Exchange Units, the managing general partner units of the Holding LP, the special general partner units of the Holding LP and any other partnership interest of the Holding LP hereafter authorized that pursuant to a written agreement with the Holding LP ranks junior to the Class A preferred limited partnership units of Holding LP in the payment of distributions and in the distribution of assets upon the dissolution, liquidation or winding-up of the Partnership, whether voluntary or involuntary.

        "Mirror Parity Securities" means any partnership interest of the Holding LP (including the Series 13 Holding LP Mirror Units and the preferred units in the capital of the Holding LP with terms designed to mirror the economic terms of the Existing Preferred Units (collectively, and together with the Series 13 Holding LP Mirror Units, the "Holding LP Mirror Units")) or the Partnership that pursuant to a written agreement with the Partnership ranks equally with the Class A preferred limited partnership units of the Holding LP in the payment of distributions and in the distribution of assets upon the dissolution, liquidation or winding-up of the Holding LP, whether voluntary or involuntary. As of the date of this prospectus supplement, 49,867,650 Mirror Parity Securities were issued and outstanding by the Holding LP, all of which were the Holding LP Mirror Units in respect of the Existing Preferred Units.

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DESCRIPTION OF LIMITED PARTNERSHIP UNITS

        We may issue LP Units in one or more offerings pursuant to this prospectus and any applicable prospectus supplement. The description of the LP Units contained in this prospectus, together with the applicable prospectus supplements and in the documents incorporated by reference herein and therein summarize or will summarize all the material terms and provisions of the LP Units, together with any material U.S. and Canadian federal income tax considerations related to such LP Units. If we indicate in the applicable prospectus supplement, the terms of the LP Units may differ from the terms we have summarized below.

        The LP Units are non-voting limited partnership interests in the Partnership. Holders of LP Units are not entitled to the withdrawal or return of capital contributions in respect of the LP Units, except to the extent, if any, that distributions are made to such holders pursuant to the Partnership's limited partnership agreement or upon the liquidation of the Partnership as described in our Annual Report or as otherwise required by applicable law. Except to the extent expressly provided in the Partnership's limited partnership agreement, a holder of LP Units will not have priority over any other holder of LP Units, either as to the return of capital contributions or as to profits, losses or distributions. The LP Units rank junior to the Preferred LP Units with respect to priority in the payment of distributions and in the distribution of the assets of the Partnership in the event of the liquidation, dissolution or winding-up of the Partnership, whether voluntary or involuntary, as further described in our Annual Report. Holders of LP Units will not be granted any preemptive or other similar right to acquire additional interests in the Partnership. In addition, holders of LP Units do not have any right to have their LP Units redeemed by the Partnership.

        For a more detailed description of the LP Units, please refer to our Annual Report, as updated by our subsequent filings with the SEC that are incorporated herein by reference.

DESCRIPTION OF PREFERRED LIMITED PARTNERSHIP UNITS

        We may issue Preferred LP Units in one or more offerings pursuant to this prospectus and any applicable prospectus supplement. The description of the Preferred LP Units contained in this prospectus, together with the applicable prospectus supplements and in the documents incorporated by reference herein and therein summarize or will summarize all the material terms and provisions of the Preferred LP Units, together with any material U.S. and Canadian federal income tax considerations relating to such Preferred LP Units. If we indicate in the applicable prospectus supplement, the terms of the Preferred LP Units may differ from the terms we have summarized below.

        We may issue additional series of the Partnership's Class A Preferred LP Units (the "Class A Preferred Units") or we may issue any other class or series of Preferred LP Units. As of June 21, 2019, the Partnership had six series of Class A Preferred Units outstanding: Series 1, Series 3, Series 5, Series 7, Series 9 and Series 11, which are listed on the TSX under the symbols "BIP.PR.A," "BIP.PR.B," "BIP.PR.C," "BIP.PR.D," "BIP.PR.E" and "BIP.PR.F," respectively. The Class A Preferred Units are non-voting limited partnership interests in the

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Partnership. Holders of Class A Preferred Units are not entitled to the withdrawal or return of capital contributions in respect of Class A Preferred Units, except to the extent, if any, that distributions are made to such holders pursuant to the Partnership's limited partnership agreement or upon the liquidation of the Partnership as described in our Annual Report or as otherwise required by applicable law. The Class A Preferred Units rank senior to the LP Units with respect to priority in the return of capital contributions or as to profits, losses or distributions. The Class A Preferred Units may be issued in series. Each series of Class A Preferred Units ranks on a parity with every other series of the Class A Preferred Units with respect to priority in the return of capital contributions or as to profits, losses or distributions.

        For a more detailed description of the Class A Preferred Units, please refer to our Annual Report, as updated by our subsequent filings with the SEC that are incorporated herein by reference.

        Further, subject to the terms of any Preferred LP Units then outstanding, our limited partnership agreement authorizes us to establish one or more classes, or one or more series of any such classes of Preferred LP Units with such designations, preferences, rights, powers and duties (which may be senior to existing classes and series of our Preferred LP Units, such as the Class A Preferred Units), as shall be determined by the General Partner in its sole discretion, including: (i) the right to share in our profits and losses or items thereof; (ii) the right to share in our distributions; (iii) the rights upon our dissolution and liquidation; (iv) whether, and the terms and conditions upon which, we may or shall be required to redeem our Preferred LP Units (including sinking fund provisions); (v) whether such Preferred LP Unit is issued with the privilege of conversion or exchange and, if so, the terms and conditions of such conversion or exchange; (vi) the terms and conditions upon which each Preferred LP Unit will be issued, evidenced by certificates and assigned or transferred; and (viii) the requirement, if any, of each such Preferred LP Unit to consent to certain partnership matters.