TNCAF TC Energy Corporation (PK)

QUESTIONS AND ANSWERS ABOUT THE MERGER AND THE SPECIAL MEETING

        The following questions and answers are intended to address briefly some commonly asked questions regarding the Merger and matters to be addressed at the special meeting. These questions and answers may not address all questions that may be important to you. To better understand these matters, and for a description of the legal terms governing the Merger, you should carefully read this entire proxy statement/prospectus, including the attached annexes, as well as the documents that have been incorporated by reference into this proxy statement/prospectus. For more information, see the section entitled "Where You Can Find Additional Information."

Q:

Why am I receiving this proxy statement/prospectus?

A:

On December 14, 2020, TC PipeLines entered into the Merger Agreement with TCP GP, TC Energy, TC Northern, TC PipeLine USA and Merger Sub providing for, among other things, the merger of Merger Sub with and into TC PipeLines, pursuant to which TC PipeLines will survive the merger as an indirect, wholly owned subsidiary of TC Energy (which we refer to in such capacity as the "surviving entity"). You are receiving this proxy statement/prospectus in connection with the solicitation by the GP Board of proxies of TC PipeLines unitholders to vote in favor of the merger proposal.

TC PipeLines is holding a special meeting to obtain the unitholder approval necessary to adopt the Merger Agreement. Approval of the merger proposal by TC PipeLines unitholders is required for the completion of the Merger.

This proxy statement/prospectus constitutes both a proxy statement of TC PipeLines and a prospectus of TC Energy. It is a proxy statement because the GP Board is soliciting proxies from the TC PipeLines unitholders. It is a prospectus because TC Energy will issue to TC PipeLines unitholders its common shares as consideration for the exchange of outstanding TC PipeLines common units in the Merger.

Your vote is very important. We encourage you to submit a proxy to have your TC PipeLines common units voted as soon as possible.

Q:

What is the Proposed Transaction?

A:

If the merger proposal is approved by TC PipeLines unitholders and the other conditions to the completion of the Merger contained in the Merger Agreement are satisfied or waived, Merger Sub will merge with and into TC PipeLines. TC PipeLines will survive the Merger as an indirect, wholly owned subsidiary of TC Energy. As a result of the Merger, each issued and outstanding publicly-held TC PipeLines common unit, will be cancelled in exchange for the right to receive 0.70 TC Energy common shares. The 17,084,831 TC PipeLines common units owned by TC Energy and its subsidiaries will remain outstanding and will not be affected by the Merger and no consideration will be delivered in respect thereof.

Q:

What will I receive as a TC PipeLines unitholder if the Merger is completed?

A:

Under the terms of the Merger Agreement, if the Merger is completed, each TC PipeLines common unit (other than TC PipeLines common units owned directly by TC Energy, TCP GP, Merger Sub or TC PipeLines, and any other direct or indirect wholly owned subsidiary of TC Energy, TCP GP, Merger Sub, or TC PipeLines, in each case not held on behalf of third parties (such units, the "eligible units")), will be automatically cancelled in exchange for the right to receive 0.70 of a validly issued, fully paid and non-assessable TC Energy common share, which we refer to as the "merger consideration."

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No fractional TC Energy common shares will be issued upon the conversion of TC PipeLines common units. All fractional TC Energy common shares that a holder of TC PipeLines common units would be otherwise entitled to receive pursuant to the Merger Agreement will be aggregated and rounded to three decimal places. Any holder of eligible units otherwise entitled to receive a fractional TC Energy common share will be entitled to receive a cash payment, without interest, rounded down to the nearest cent, in lieu of any such fractional share, which payment will be calculated by the exchange agent and will represent such holder's proportionate interest in an TC Energy common share based on the average (rounded to the nearest thousandth) of the closing trading prices of TC Energy common shares on the NYSE, as reported by Bloomberg L.P. for the 10 trading days ending on the trading day that is five business days prior to the closing date. No holder of eligible units will be entitled by virtue of the right to receive cash in lieu of fractional TC Energy common shares to any dividends, voting rights or any other rights in respect of any fractional TC Energy common share.

Based on the closing price of TC Energy common shares on the NYSE on December 14, 2020, the last full trading day before the announcement of the Merger Agreement, the per unit value of TC PipeLines common units implied by the merger consideration was $30.95. Based on the closing price of TC Energy common shares on the NYSE on January 22, 2021, the most recent practicable date prior to the date of this proxy statement/prospectus, the per unit value of TC PipeLines common units implied by the merger consideration was $31.05. The implied value of the merger consideration will fluctuate, however, as the market price of TC Energy common shares fluctuates, because the merger consideration that is payable per TC PipeLines common unit is a fixed fraction of an TC Energy common share. As a result, the value of the merger consideration that TC PipeLines unitholders will receive upon the completion of the Merger could be greater than, less than or the same as the value of the merger consideration on the date of this proxy statement/prospectus or at the time of the special meeting. Accordingly, you are encouraged to obtain current price quotations for TC PipeLines common units and TC Energy common shares before deciding how to vote with respect to the merger proposal. TC PipeLines common units trade on the NYSE under the ticker symbol "TCP" and TC Energy common shares trade on the NYSE and the TSX under the ticker symbol "TRP". The price of TC Energy common shares on the NYSE is reported in U.S. dollars, while the price of TC Energy common shares on the TSX is reported in Canadian dollars.

Q:

What will happen to future distributions on my TC PipeLines common units?

A:

Prior to the closing of the Merger, TC Energy and TC Pipelines will coordinate with respect to the declaration and setting of record dates and payment dates of distributions and dividends, as applicable, on the TC Pipelines common units and TC Energy common shares so that TC Pipelines unitholders do not receive distributions and dividends, as applicable, on both TC Pipelines common units and TC Energy common shares received in the Merger in respect of any calendar quarter or fail to receive a distribution or dividend for all completed calendar quarters on either TC Pipelines common units or TC Energy common shares received in the Merger, as applicable.

Once the Merger is completed, former TC PipeLines unitholders who hold their TC PipeLines common units as of the record date and surrender their TC PipeLines common units in accordance with the Merger Agreement will be eligible, in their capacity as TC Energy shareholders, to receive dividends declared by the board of directors of TC Energy (the "TC Energy Board") on TC Energy common shares, if any, after the effective time of the Merger. TC Energy has a sustained track record of declaring dividends on TC Energy common shares and expects that it will continue to do so; however, the TC Energy Board has not adopted a formal dividend policy and there is no guarantee that the TC Energy Board will, in the future, declare

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dividends on TC Energy common shares. See the section titled "Comparative Per Share and Per Unit Market Price Information."

Q:

When and where is the special meeting?

A:

The special meeting will be held virtually via live webcast online at www.meetingcenter.io/203568828 at 10:00 a.m., Central Time, on February 26, 2021. Online access will begin at 9:45 a.m., Central Time, and TC PipeLines encourages its unitholders to access the meeting prior to the start time.

TC PipeLines has chosen to hold the special meeting solely via the Internet and not in a physical location given the public health impact of coronavirus (COVID-19) and the desire to promote the health and safety of its respective unitholders, directors, officers, employees and other constituents.

Even if you plan to attend the special meeting, TC PipeLines recommends that you vote your common units in advance as described above so that your vote will be counted if you later decide not to or become unable to attend the special meeting.

Q:

Who is entitled to vote at the special meeting?

A:

Only holders of TC PipeLines common units as of the close of business in New York, New York on January 15, 2021, which is the record date for the special meeting, are entitled to vote at the special meeting and any adjournment or postponement thereof. As of the record date, there were 71,306,396 TC PipeLines common units outstanding. Each outstanding TC PipeLines common unit is entitled to one vote on each matter coming before TC PipeLines unitholders at the special meeting.

Q:

Who may attend the special meeting?

A:

Unitholders as of the close of business on the record date may attend, vote and submit questions virtually at the special meeting by accessing www.meetingcenter.io/203568828 and entering the 15-digit control number on the proxy card previously received and the special meeting password, TCP2021.

If you hold your TC PipeLines common units through an intermediary, such as a bank or broker, you must register in advance to attend the special meeting. To register to attend the special meeting online by webcast you must submit proof of your proxy power (legal proxy) reflecting your TC PipeLines holdings along with your name and email address to Computershare. Requests for registration should be directed to Computershare by forwarding the email you received from your bank or broker, or an image of your legal proxy, to legalproxy@computershare.com. Requests for registration must be labeled as "Legal Proxy" and be received no later than 8:00 a.m., Central Time, on February 23, 2021. You will receive a confirmation of your registration by email after your registration materials have been received. At the time of the special meeting, go to www.meetingcenter.io/203568828 and enter your control number and the special meeting password, TCP2021.

If you would like to enter the meeting as a guest in listen-only mode, click on the "I am a guest" button after entering the meeting center at www.meetingcenter.io/203568828 and enter the information requested on the following screen. Please note you will not have the ability to ask questions or vote during the special meeting if you participate as a guest.

Q:

What am I being asked to vote on?

A:

You are being asked to approve and adopt the Merger Agreement, pursuant to which Merger Sub will merge with and into TC PipeLines. TC PipeLines will survive the Merger as an indirect, wholly

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owned subsidiary of TC Energy. The approval of the merger proposal is a condition to the obligations of TC PipeLines and TC Energy to complete the Merger.

Q:

What vote is required to approve the merger proposal?

A:

The approval of the merger proposal requires the affirmative vote of the holders of a majority of the outstanding TC PipeLines common units entitled to vote on the merger proposal.

Q:

Does the GP Board recommend that TC PipeLines unitholders approve the Merger Agreement and the Merger?

A:

Yes. The GP Board recommends that TC PipeLines unitholders vote "FOR" the merger proposal.

The Conflicts Committee unanimously determined that the Merger Agreement and the transactions contemplated thereby, including the Merger, are fair and reasonable to, and in the best interests of, TC PipeLines and the Unaffiliated TCP Unitholders, and approved the Merger Agreement and the transactions contemplated thereby, including the Merger, on the terms and subject to the conditions set forth in the Merger Agreement. This action of the Conflicts Committee constitutes "Special Approval" of the Merger Agreement and the transactions contemplated thereby, including the Merger, under the TCP Partnership Agreement. The Conflicts Committee recommended that (i) the GP Board approve the Merger Agreement and the transactions contemplated thereby, including the Merger, (ii) the GP Board approve the execution, delivery and performance of the Merger Agreement and the consummation of the transactions contemplated thereby, including the Merger, and (iii) the GP Board recommend that the limited partners of TC PipeLines approve the Merger Agreement and the transactions contemplated thereby, including the Merger, and direct that the Merger Agreement be submitted to a vote of the limited partners of TC PipeLines for their approval at a special meeting and that the GP Board recommend to the limited partners that the limited partners approve the Merger Agreement and the Merger. Based upon the recommendation of the Conflicts Committee, the GP Board unanimously (i) determined that the Merger Agreement and the transactions contemplated by the Merger Agreement, including the Merger, are fair and reasonable to, and in the best interests of, TC PipeLines and the Unaffiliated TCP Unitholders, (ii) approved the Merger Agreement and the transactions contemplated thereby, including the Merger, on the terms and subject to the conditions set forth in the Merger Agreement, and (iii) approved the execution, delivery and performance of the Merger Agreement and the consummation of the transactions contemplated thereby, including the Merger. The GP Board directed that the Merger Agreement be submitted to the limited partners of TC PipeLines for their approval at the special meeting. Accordingly, the GP Board recommends that you vote "FOR" the merger proposal.

For a discussion of the merger proposal, see the section entitled "The Merger Proposal—Recommendation of the Conflicts Committee," "—Recommendation of the GP Board" and "—Reasons for the Recommendation of the Conflicts Committee."

Q:

How do I vote my common units?

A:

If you are a unitholder of record of TC PipeLines as of the close of business on the record date, you may submit your proxy before the special meeting in one of the following ways:

•

Telephone—use the toll-free number shown on your proxy card;

•

Internet—visit the website shown on your proxy card to vote via the internet; or

•

Mail—complete, sign, date and return the enclosed proxy card in the enclosed postage-paid envelope.

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If you are a unitholder of record, you may also cast your vote virtually at the special meeting by following the instructions in this proxy statement/prospectus. See the section entitled "The Special Meeting—Attendance at the Special Meeting and Voting Virtually—Attending the Special Meeting as Unitholder of Record." If you decide to attend the special meeting virtually and vote at the meeting, your vote will revoke any proxy previously submitted.

If your common units are held in "street name" through a broker, bank or other nominee, that institution will send you separate instructions describing the procedure for voting your common units. If your common units are held in "street name" and you intend to vote at the special meeting, you may cast your vote virtually at the special meeting by following the instructions in this proxy statement/prospectus. See the section entitled "The Special Meeting—Attendance at the Special Meeting and Voting Virtually—Registering to Attend the Special Meeting as a Beneficial Owner." Your vote at the special meeting will revoke any proxy previously submitted on your behalf by your broker, bank or other nominee.

The special meeting will begin promptly at 10:00 a.m., Central Time, on February 26, 2021. TC PipeLines encourages its unitholders to access the meeting prior to the start time leaving ample time for check-in. Please follow the instructions as outlined in this proxy statement/prospectus.

Even if you plan to attend the special meeting, TC PipeLines recommends that you vote your common units in advance as described below so that your vote will be counted even if you later decide not to or become unable to attend the special meeting.

Q:

What is a proxy?

A:

A proxy is your legal designation of another person, referred to as a "proxy," to vote your TC PipeLines common units. The written document describing the matters to be considered and voted on at the special meeting is called a "proxy statement." The document used to designate a proxy to vote your TC PipeLines common units is called a "proxy card." See "The Special Meeting."

Q:

If I am not going to attend the special meeting, should I return my proxy card or otherwise vote my common units?

A:

Yes. Completing, signing, dating and returning the proxy card by mail or submitting a proxy by calling the toll-free number shown on the proxy card or submitting a proxy by visiting the website shown on the proxy card ensures that your common units will be represented and voted at the special meeting, even if you otherwise do not attend.

Q:

If my units are held in "street name" by my bank, broker or other nominee, will the bank, broker or other nominee vote my common units for me?

A:

A bank, broker or other nominee will vote your common units only if you provide instructions to the bank, broker or other nominee on how to vote. You should follow the directions provided by your bank, broker or other nominee regarding how to instruct the bank, broker or other nominee to vote your common units. If you fail to instruct your bank, broker or other nominee how to vote, that failure will have the same effect as a vote "AGAINST" the merger proposal.

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Q:

Can I change my vote?

A:

Yes. If you are a TC PipeLines unitholder of record and have properly completed and submitted your proxy card or proxy by telephone or the Internet, you can change your vote in any of the following ways:

•

Sending a written notice (bearing a date later than the date of the proxy) stating that you revoke your proxy to TC PipeLines at 700 Louisiana Street, Suite 1300, Houston, Texas 77002-2761, Attn: Secretary;

•

Submitting a valid, later-dated proxy by mail, telephone or the Internet; or

•

Voting virtually at the special meeting.

If you choose to revoke your proxy by written notice or submit a later-dated proxy, you must do so by 11:59 p.m. Central Time on February 25, 2021.

If your common units are held in "street name" by your bank, broker or other nominee and you have directed such bank, broker or other nominee to vote your common units, you should instruct such bank, broker or other nominee to change your vote and follow the directions you receive from your bank, broker or other nominee in order to change or revoke your vote.

Q:

What if I do not vote?

A:

If you fail to submit your proxy, fail to vote your common units, abstain from voting or fail to instruct your broker, bank or other nominee how to vote, that failure will have the same effect as a vote "AGAINST" the merger proposal.

If you submit your proxy card but do not indicate how you want to vote on the merger proposal, your proxy will be counted as a vote "FOR" that proposal.

Q:

What should I do now?

A:

After carefully reading and considering the information contained in this proxy statement/prospectus, you should submit a proxy by mail, by telephone or the Internet to vote your common units as soon as possible so that your common units will be represented and voted at the special meeting. You should follow the instructions set forth on the enclosed proxy card or on the voting instruction form provided by the record holder if your common units are held in the name of a bank, broker or other nominee.

Q:

What constitutes a quorum?

A:

A quorum is the number of TC PipeLines common units that must be present virtually or by proxy, in order for business to be transacted at a meeting of TC PipeLines unitholders. The required quorum for the special meeting is the holders of a majority of the outstanding TC PipeLines common units entitled to vote as of the record date. All common units represented at the special meeting virtually or by proxy (including those voted by telephone or the Internet) will be counted toward the quorum. Common units held by TC PipeLines unitholders who mark their proxy card "ABSTAIN," vote "ABSTAIN" by telephone or the Internet, instruct their bank, broker or other nominee to vote units held in "street name" to "ABSTAIN" or appear at the special meeting without otherwise voting their common units will be treated as common units represented at the meeting for purposes of determining the presence of a quorum. Common units held by TC PipeLines unitholders who do not attend the special meeting and do not submit a proxy, vote by telephone or the Internet or give voting instructions with respect to their common units will not be treated as represented at the special meeting for purposes of determining the presence of a quorum.

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TC PipeLines common units held in "street name" with respect to which the beneficial owner fails to give voting instructions to the bank, broker or nominee, and TC PipeLines common units with respect to which the beneficial owner otherwise fails to vote, will not be considered present and entitled to vote at the special meeting for the purpose of determining the presence of a quorum.

Q:

Is my vote important?

A:

Yes. Your vote is very important. The Merger cannot be completed without the approval of the merger proposal by TC PipeLines unitholders. The approval of the merger proposal requires the affirmative vote of the holders of a majority of the outstanding TC PipeLines common units entitled to vote at the special meeting. The GP Board recommends that you vote "FOR" the merger proposal.

Q:

What happens if I transfer or sell my common units before the special meeting or before completion of the Merger?

A:

The record date is earlier than the date of the special meeting and the date that the Merger is expected to be completed. If you transfer or sell your common units after the record date but before the special meeting, you will retain your right to vote at the special meeting. However, if you are a TC PipeLines unitholder, you will have transferred the right to receive the merger consideration in the Merger. In order to receive the merger consideration, you must hold your common units through the effective time of the Merger.

Q:

What if I receive more than one set of voting materials?

A:

You may receive more than one set of voting materials, including multiple copies of this proxy statement/prospectus, the proxy card or the voting instruction form. This can occur if you hold your common units in more than one brokerage account, if you hold common units directly as a holder of record and also in "street name," or otherwise through another holder of record, and in certain other circumstances. If you receive more than one set of voting materials, please vote or return each set separately in order to ensure that all of your common units are voted.

Q:

Where can I find the voting results of the special meeting?

A:

The preliminary voting results will be announced at the special meeting. In addition, within four business days following certification of the final voting results, TC PipeLines intends to file the final voting results with the SEC on a Current Report on Form 8-K.

Q:

What will happen if the merger proposal is not approved?

A:

As a condition to the completion of the Merger, TC PipeLines unitholders must approve the merger proposal. If the merger proposal is not approved by the TC PipeLines unitholders, the Merger will not be completed.

Q:

How will directors and executive officers of TCP GP vote on the merger proposal?

A:

It is expected that the directors and executive officers of TCP GP who are TC PipeLines unitholders will vote "FOR" the merger proposal, although none of them has entered into any agreement requiring them to do so.

As of the record date for the special meeting, the directors and executive officers of TCP GP owned, in the aggregate, approximately 1,290 TC PipeLines common units, representing less than 1% of the TC PipeLines common units then outstanding and entitled to vote at the special meeting.

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Q:

Do any of directors or executive officers of TCP GP have interests in the Merger that may differ from or be in addition to my interests as a unitholder?

A:

Yes. In considering the recommendation of the Conflicts Committee with respect to the Merger and the GP Board with respect to the merger proposal, you should be aware that the directors and executive officers of TCP GP have interests in the Merger that are different from, or in addition to, the interests of TC PipeLines unitholders generally. The GP Board was aware of those interests and considered them, among other matters, in approving the Merger Agreement, the Merger, and the other transactions contemplated by the Merger Agreement. For a discussion of TCP GP's directors' or executive officers' interests in the Merger that may differ from or be in addition to your interests as a common unitholder, see the section entitled "The Merger Proposal—Interests of the Directors and Executive Officers of TCP GP in the Merger."

Q:

Is the obligation of each of TC PipeLines and TC Energy to complete the Merger subject to any conditions?

A:

Yes. Completion of the Merger is subject to the satisfaction or waiver of a number of conditions as set forth in the Merger Agreement, including, among others, (i) the adoption of the Merger Agreement by an affirmative vote of the holders of a majority of all of the outstanding TC PipeLines units entitled to vote at the special meeting, (ii) the approval in connection with the Merger for listing on the NYSE and the TSX of the TC Energy common shares to be issued to TC PipeLines unitholders in connection with the Merger, subject to official notice of issuance, (iii) the expiration or early termination of the applicable waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended (the "HSR Act") and any required approval or consent under any other applicable antitrust law must have been obtained, (iv) the approval of the Committee on Foreign Investment in the United States ("CFIUS") pursuant to Section 721 of the Defense Production Act of 1950, as amended (the "DPA"), (v) no governmental entity of competent jurisdiction shall have enacted, issued, promulgated, enforced or entered any law or governmental order (whether temporary, preliminary or permanent) that is in effect and restrains, enjoins, makes illegal or otherwise prohibits the consummation of the transactions contemplated by the merger agreement, (vi) the registration statement of which this proxy statement/prospectus forms a part having been declared effective by the SEC and (vii) other customary closing conditions, including the accuracy of each party's representations and warranties (subject to specified materiality qualifiers), and each party's material compliance with its covenants and agreements contained in the Merger Agreement. For a more detailed discussion of the conditions to the completion of the Merger, see the section entitled "The Merger Agreement—Conditions to the Completion of the Merger."

Q:

Will the TC Energy common shares to be issued to me at the completion of the Merger be traded on an exchange?

A:

Yes. It is a condition to the completion of the Merger that the TC Energy common shares to be issued to TC PipeLines unitholders in connection with the Merger be approved for listing on the NYSE and the TSX, subject to official notice of issuance. Therefore, at the effective time of the Merger, all TC Energy common shares received by TC PipeLines unitholders in connection with the Merger will be listed on both the TSX and the NYSE under the ticker symbol "TRP" and may be traded by shareholders on either exchange.

TC Energy common shares received by TC PipeLines unitholders in connection with the Merger will be freely transferable except for shares issued to any shareholder deemed to be an "affiliate" of TC Energy for purposes of U.S. federal securities law. For more information, see the section entitled "The Merger Proposal—Restrictions on Resales of TC Energy Common Shares Received in the Merger."

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Q:

What are the expected U.S. federal income tax consequences to a TC PipeLines unitholder as a result of the Merger?

A:

The receipt of TC Energy common shares and cash in lieu of fractional shares, if any, in exchange for TC PipeLines common units pursuant to the Merger Agreement is expected to be a taxable transaction to U.S. holders (as defined in the section titled "Material U.S. Federal Income Tax Consequences of the Merger") for U.S. federal income tax purposes. In such case, a U.S. holder will generally recognize gain or loss in connection with the receipt of TC Energy common shares and/or any cash received in lieu of fractional shares in exchange for its TC PipeLines common units and any reduction in such U.S. holder's share of TC PipeLines' nonrecourse liabilities immediately prior to the Merger, generally taxable as capital gain or loss. However, a portion of this gain or loss, which portion could be substantial, will be separately computed and taxed as ordinary income or loss to the extent attributable to assets giving rise to depreciation recapture or other "unrealized receivables" or to "inventory items" owned by TC PipeLines and its subsidiaries. For U.S. holders subject to the passive loss rules, passive losses that were not deductible by a U.S. holder in prior taxable periods may become available to offset a portion of the gain recognized by such U.S. holder. See the section titled "Material U.S. Federal Income Tax Consequences of the Merger" for a more complete discussion of the expected material U.S. federal income tax consequences of the Merger.

Q:

What are the expected U.S. federal income tax consequences for a TC PipeLines unitholder as a result of the ownership of TC Energy common shares after the Merger is completed?

A:

TC Energy is a corporation organized under the laws of Canada that is treated as a corporation for U.S. federal income tax purposes, and thus, the TC Energy shareholders are generally not directly subject to U.S. federal income tax on TC Energy's income. A distribution of cash (including any portion of the distribution that is required to be withheld with respect to Canadian federal income taxes, as discussed below) by TC Energy to a shareholder who is a U.S. holder (as defined in the section titled "Material U.S. Federal Income Tax Consequences of the Merger") will generally be included in such U.S. holder's income as ordinary dividend income to the extent of TC Energy's current and accumulated "earnings and profits" as determined under U.S. federal income tax principles. Any portion of such distribution to TC Energy shareholders by TC Energy after the Merger that exceeds TC Energy's current and accumulated earnings and profits will be treated as a non-taxable return of capital reducing a U.S. holder's adjusted tax basis in such U.S. holder's TC Energy common shares and, to the extent the distribution exceeds such shareholder's adjusted tax basis, as capital gain from the sale or exchange of such TC Energy common shares. However, consistent with many similarly situated non-U.S. corporations, TC Energy does not expect to calculate earnings and profits in accordance with U.S. federal income tax principles. Accordingly, each TC Energy shareholder generally should expect distributions (including any portion of a distribution that is required to be withheld with respect to Canadian federal income taxes, as discussed below) made by TC Energy to be reported to them as dividends. See the section titled "Material U.S. Federal Income Tax Consequences of the Merger" for a more complete discussion of the expected U.S. federal income tax consequences of owning and disposing of TC Energy common shares received in the Merger.

Q:

What are the expected Canadian federal income tax consequences for a TC PipeLines unitholder as a result of the ownership of TC Energy common shares after the Merger is completed?

A:

Dividends paid or credited or deemed to be paid or credited on TC Energy common shares to a Non-Canadian Resident Holder (as defined in the section titled "Material Canadian Federal Income Tax Consequences of the Merger" generally will be subject to Canadian withholding tax at a rate of 25% of the gross amount of the dividend, unless the rate is reduced under the provisions of an

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applicable income tax convention between Canada and the Non-Canadian Resident Holder's jurisdiction of residence. For example, the rate of withholding tax under the Canada-United States Income Tax Convention (1980) Treaty (the "Treaty") applicable to a Non-Canadian Resident Holder who is a resident of the United States for purposes of the Treaty, is the beneficial owner of the dividend and is entitled to all of the benefits under the Treaty, generally will be 15%. TC Energy will be required to withhold the required amount of withholding tax from the dividend, and to remit the withheld tax to the Canada Revenue Agency (the "CRA") for the account of the Non-Canadian Resident Holder.

A Non-Canadian Resident Holder will not be subject to tax under the Income Tax Act (Canada) including the regulations thereunder, as amended from time to time (which is referred to as the "Canadian Tax Act"), on any capital gain realized on a disposition of TC Energy common shares, unless the shares are "taxable Canadian property" and the shares are not "treaty-protected property" (as those terms are defined in the Canadian Tax Act) of the Non-Canadian Resident Holder, at the time of the disposition. See the section titled "Material Canadian Federal Income Tax Consequences of the Merger" for a more complete discussion of the expected Canadian federal income tax consequences of owning and disposing of TC Energy common shares received in the Merger.

Q:

Are there risks associated with the Merger?

A:

Yes. There are important risks involved. Before making any decision on whether and how to vote, you are urged to read carefully and in its entirety the section entitled "Risk Factors."

Q:

Do I have appraisal or dissenters' rights for my TC PipeLines common units in connection with the Merger?

A:

No. Holders of TC PipeLines common units do not have appraisal or dissenters' rights under applicable law or contractual appraisal rights under the TCP Partnership Agreement or the Merger Agreement.

Q:

When will the Merger be completed?

A:

TC PipeLines and TC Energy are working to complete the Merger as quickly as possible. In addition to regulatory approvals, and assuming that the merger proposal is approved by TC PipeLines unitholders at the special meeting, other important conditions to the completion of the Merger exist. Assuming the satisfaction of all necessary conditions, TC PipeLines and TC Energy expect to complete the Merger late in the first quarter or early in the second quarter of 2021. The Merger Agreement contains an outside date of August 14, 2021 for the completion of the Merger, which may be extended by either TC PipeLines or TC Energy in certain circumstances, which we refer to as the "outside date." For a discussion of the conditions to the completion of the Merger, see the sections entitled "The Merger Proposal—Regulatory Approvals Required for the Merger" and "The Merger Agreement—Conditions to the Completion of the Merger."

Q:

What happens if the Merger is not completed?

A:

If the Merger is not completed for any reason, you will not receive any consideration for your TC PipeLines common units, TC PipeLines will remain a publicly traded limited partnership and TC PipeLines common units will continue to be listed and traded on the NYSE.

Q:

Who will solicit and pay the cost of soliciting proxies?

A:

TC PipeLines will bear all costs and expenses in connection with the solicitation of proxies from its unitholders, except that TC PipeLines and TC Energy have agreed to share equally the expenses of

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printing and mailing this proxy statement/prospectus and all filing fees payable to the SEC in connection with this proxy statement/prospectus. In addition to the solicitation of proxies by mail, TC PipeLines will request that banks, brokers and other record holders send proxies and proxy material to the beneficial owners of TC PipeLines common units and secure their voting instructions, if necessary. TC PipeLines will reimburse the banks, brokers and other record holders for their reasonable expenses in taking those actions. TC PipeLines has also made arrangements with Morrow Sodali LLC to assist in soliciting proxies and in communicating with TC PipeLines unitholders and estimates that it will pay Morrow Sodali LLC a fee of approximately $20,000 plus reasonable out-of-pocket fees and expenses for these services. Proxies may also be solicited by TC PipeLines' directors, officers and other employees through the mail or by telephone, the Internet, fax or other means, but no additional compensation will be paid to these persons.

Q:

What is "householding"?

A:

The SEC has adopted a rule concerning the delivery of annual reports and proxy statements. It permits TC PipeLines, with your permission, to send a single notice of meeting and, to the extent requested, a single set of this proxy statement/prospectus to any household at which two or more unitholders reside if TC PipeLines believes they are members of the same family. This rule is called "householding," and its purpose is to help reduce printing and mailing costs of proxy materials. A number of brokerage firms have instituted householding. If you and members of your household have multiple accounts holding TC PipeLines common units, you may have received a householding notification from your broker. Please contact your broker directly if you have questions, require additional copies of this proxy statement/prospectus or wish to revoke your decision to household. These options are available to you at any time.

Q:

Is the exchange ratio subject to adjustment based on changes in the prices of TC PipeLines common units or TC Energy common shares? Can it be adjusted for any other reason?

A:

As merger consideration, you will receive a fixed number of TC Energy common shares, not a number of shares that will be determined based on a fixed market value. The market value of TC Energy common shares and the market value of TC PipeLines common units at the effective time may vary significantly from their respective values on the date that the Merger Agreement was executed or at other dates, such as the date of this proxy statement/prospectus or the date of the special meeting. Stock price changes may result from a variety of factors, including changes in TC Energy's or TC PipeLines' respective businesses, operations or prospects, regulatory considerations, and general business, market, industry or economic conditions. The exchange ratio will not be adjusted to reflect any changes in the market value of TC Energy common shares, the comparative value of the Canadian dollar and U.S. dollar or market value of the TC PipeLines common units. Therefore, the aggregate market value of the TC Energy common shares that a TC PipeLines unitholder is entitled to receive at the time that the Merger is completed could vary significantly from the value of such shares on the date of this proxy statement/prospectus, the date of the special meeting or the date on which a TC PipeLines unitholder actually receives its TC Energy common shares.

However, the merger consideration will be equitably adjusted to provide you and TC Energy with the same economic effect as contemplated by the Merger Agreement in the event of any reclassification, stock or unit split (including a reverse stock or unit split), stock dividend or common unit distribution, recapitalization, merger or other similar transaction involving TC PipeLines common units or TC Energy common shares prior to the completion of the Merger.

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Q:

Who can answer my questions?

A:

If you are a TC PipeLines unitholder and you have any questions about the Merger or you would like to request additional documents, including copies of this proxy statement/prospectus, please contact TC PipeLines' proxy solicitor:

Morrow Sodali LLC
509 Madison Avenue, Suite 1206
New York, New York 10022
(800) 662-5200 (toll-free from the U.S. and Canada)
+1 (203) 658-9400 (from other locations)
Email: TCP@investor.morrowsodali.com

Q:

Where can I find more information about TC PipeLines, TC Energy and the transactions contemplated by the Merger Agreement?

A:

You can find out more information about TC PipeLines, TC Energy and the transactions contemplated by the Merger Agreement by reading this proxy statement/prospectus and, with respect to TC PipeLines and TC Energy, from various sources described in the section entitled "Where You Can Find Additional Information."

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