As filed with the Securities and Exchange Commission on October 10, 2018

Registration No. 333-            

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM S-4

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

ENBRIDGE INC.

(Exact Name of Registrant as Specified in Its Charter)

200, 425 - 1st Street S.W.

Calgary, Alberta T2P 3L8, Canada

Telephone: 1-403-231-3900

(Address, including Zip Code, and Telephone Number, including Area Code, of Registrant’s Principal Executive Offices)

Kelly L. Gray

Enbridge (U.S.) Inc.

5400 Westheimer Court

Houston, Texas 77056

(713) 627-5400

(Name, Address, including Zip Code, and Telephone Number, including Area Code, of Agent for Service)

With copies to:

Approximate date of commencement of proposed sale of the securities to the public: As soon as practicable after this registration statement is declared effective and upon consummation of the merger described in the enclosed proxy statement/prospectus.

If the securities being registered on this form are being offered in connection with the formation of a holding company and there is compliance with General Instruction G, please check the following box.

If this form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act of 1933, as amended (the “Securities Act”), check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ☐

If this form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer”, “accelerated filer”, “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act. (Check one):

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act.  ☐

If applicable, place an X in the box to designate the appropriate rule provision relied upon in conducting this transaction:

Exchange Act Rule 13e-4(i) (Cross-Border Issuer Tender Offer)  ☐

Exchange Act Rule 14d-1(d) (Cross-Border Third-Party Tender Offer)  ☐

CALCULATION OF REGISTRATION FEE

The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933, as amended, or until the registration statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

The information in this document is not complete and may be changed. The securities described herein may not be sold until the registration statement filed with the Securities and Exchange Commission is effective. This document is not an offer to sell these securities and it is not soliciting an offer to buy these securities in any state where the offer or sale is not permitted.

PRELIMINARY PROXY STATEMENT/PROSPECTUS SUBJECT TO COMPLETION, DATED

OCTOBER 10, 2018

ENBRIDGE ENERGY PARTNERS, L.P.

MERGER PROPOSAL—YOUR VOTE IS VERY IMPORTANT

[                    ]

To the Unitholders of Enbridge Energy Partners, L.P.:

On September 17, 2018, Enbridge Energy Partners, L.P., which is referred to as “EEP”, entered into an Agreement and Plan of Merger (which, as may be amended from time to time, is referred to as the “Merger Agreement”) with the general partner of EEP, which is Enbridge Energy Company, Inc. (the “General Partner”), Enbridge Energy Management, L.L.C., which is the delegate of the General Partner (the “GP Delegate” or “EEQ”), Enbridge Inc. (“Enbridge”), Enbridge (U.S.) Inc., Winter Acquisition Sub II, LLC (“Merger Sub”) and, solely for the purposes of Article I, Article II and Article XI therein, Enbridge US Holdings Inc. The Merger Agreement provides that Merger Sub will be merged with and into EEP, with EEP being the surviving entity and becoming an indirect wholly owned subsidiary of Enbridge (the “Merger”). As a result of the Merger, Enbridge will acquire indirectly all of the outstanding Class A common units representing limited partner interests in EEP (the “Class A common units”) that Enbridge and its subsidiaries do not already own.

A special committee composed of independent members of the board of directors of the GP Delegate, which is referred to as the “Special Committee”, the board of directors of the GP Delegate, which is referred to as the “GP Delegate Board”, and the board of directors of the General Partner, which is referred to as the “GP Board”, each have determined that the Merger is fair and reasonable to EEP, including the holders of the outstanding units of EEP (other than Enbridge and its affiliates), and have approved the Merger Agreement and the Merger. The approval of the Merger Agreement and the Merger by EEP requires the affirmative vote of (1) the holders of at least 66 ²⁄₃% of the outstanding EEP units (excluding the Class F units of EEP), and (2) the holders of a majority of the outstanding Class A common units (other than any Class A common units held by Enbridge and its affiliates) and the outstanding i-units (other than i-units voted at the direction of Enbridge and its affiliates), voting together as a single class, in each case entitled to vote on such matter at the special meeting or any adjournment or postponement thereof.

If the Merger is successfully completed, each outstanding Class A common unit not owned by Enbridge or any of its subsidiaries will be converted into the right to receive 0.335 of an Enbridge common share, which common shares are referred to as “Enbridge common shares” and such exchange ratio is referred to as the “Exchange Ratio”. Based on the number of Enbridge common shares and Class A common units that are outstanding as of October 2, 2018 (other than any Class A common units owned by Enbridge or its subsidiaries), the number of Enbridge common shares issued in exchange for Class A units as a result of the proposed Merger would represent approximately 4.0% of the Enbridge common shares outstanding (or approximately 3.6% if the proposed Merger and the Other Merger Transactions were successfully completed, based on the number of Enbridge common shares expected to be issued in the proposed Merger and the Other Merger Transactions (as defined and described below) in accordance with the respective transaction agreements, and the number of outstanding Enbridge common shares and outstanding shares or units, as the case may be, of each of EEP, EEQ, SEP and ENF (each of SEP and ENF, as defined below), as of October 2, 2018). The actual number of Enbridge common shares issued in the Merger will be determined by multiplying the Exchange Ratio by the number of issued and outstanding Class A common units held by Unaffiliated EEP Unitholders as of the closing date of the Merger. The actual number of Enbridge common shares issued in each of the Other Merger Transactions will be determined by multiplying the applicable exchange ratio by the number of publicly held shares or units of the acquired entity as of the closing date of each such transaction.

Enbridge has also entered into definitive agreements to acquire, in separate combination transactions, all of the outstanding equity securities that Enbridge does not already own of (1) the GP Delegate, (2) Spectra Energy Partners, LP (“SEP”), and (3) Enbridge Income Fund Holdings Inc. (“ENF”), which transactions are referred to separately as the “EEQ merger”, the “SEP merger” and the “ENF plan of arrangement”, respectively, and collectively as the “Other Merger Transactions”.

Each of EEQ and ENF will hold a special meeting of its shareholders to obtain their approval of the applicable merger agreement or plan of arrangement. SEP will solicit consents in order to obtain the requisite approval of the SEP unitholders. Completion of the EEQ merger is contingent on the completion of the Merger, while none of the Merger, the SEP merger or the ENF plan of arrangement are conditioned on the completion of any of the Other Merger Transactions. The consents of Enbridge and its subsidiaries (other than SEP) to the SEP merger are sufficient to approve the SEP merger and the related merger agreement.

We are holding a special meeting of EEP unitholders on [            ], [            ] at [            ], local time, at 5400 Westheimer Court, Houston, Texas 77056, to obtain your vote to approve the Merger Agreement. Your vote is very important, regardless of the number of EEP units that you own. The Merger cannot be completed unless two-thirds of the outstanding EEP units (excluding the Class F units of EEP) and a majority of the outstanding Class A common units and i-units (other than Class A common units held by or i-units voted at the direction of Enbridge and its affiliates, and voting as a single class) are voted for the approval of the Merger Agreement at the special meeting. Therefore, your failure to vote your EEP units will have the same effect as a vote against approval of the Merger Agreement.

The Special Committee, the GP Delegate Board and the GP Board each recommend that EEP unitholders vote FOR the approval of the Merger Agreement, and the GP Delegate Board and the GP Board each recommend that EEP unitholders vote FOR the adjournment of the special meeting from time to time if necessary to solicit additional proxies if there are not sufficient votes to approve the Merger Agreement at the time of the special meeting.

The Class A common units are traded on the New York Stock Exchange (the “NYSE”) under the symbol “EEP”, and the Enbridge common shares are traded on the NYSE and the Toronto Stock Exchange (the “TSX”) under the symbol “ENB”. The last reported sale price of Enbridge common shares on the NYSE on October 9, 2018, was US$33.70. The last reported sale price of the Class A common units on the NYSE on October 9, 2018, was US$11.40.

On behalf of the GP Board, I invite you to attend the special meeting. Whether or not you expect to attend the special meeting in person, we urge you to submit your proxy as promptly as possible through one of the delivery methods described in the accompanying proxy statement/prospectus.

In addition, we urge you to read carefully the accompanying proxy statement/prospectus (and the documents incorporated by reference into it), which includes important information about the Merger Agreement, the proposed Merger, the Other Merger Transactions and the special meeting. Please pay particular attention to the section titled “Risk Factors” beginning on page [        ] of the accompanying proxy statement/prospectus.

On behalf of the GP Board, thank you for your continued support.

Sincerely,

Jeffrey A. Connelly

Chairman of the Board of Directors

Enbridge Energy Company, Inc., as the general

partner of Enbridge Energy Partners, L.P.

NEITHER THE U.S. SECURITIES AND EXCHANGE COMMISSION NOR ANY STATE SECURITIES COMMISSION HAS APPROVED OR DISAPPROVED OF THE MERGER, THE APPROVAL OF THE MERGER AGREEMENT, THE ISSUANCE OF ENBRIDGE COMMON SHARES IN CONNECTION WITH THE MERGER OR ANY OTHER MERGER TRANSACTIONS DESCRIBED IN THE ACCOMPANYING PROXY STATEMENT/PROSPECTUS, OR PASSED UPON THE ADEQUACY OR ACCURACY OF THE DISCLOSURE IN THIS DOCUMENT. ANY REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.

The enforcement by investors of civil liabilities under United States federal securities laws may be affected adversely by the fact that Enbridge is incorporated under the laws of Canada, that at certain points in time, most of its officers and directors may be residents of Canada, that some of the experts named in the accompanying proxy statement/prospectus are residents of Canada, and that all or a substantial portion of the assets of Enbridge and said persons are located outside the United States.

The accompanying proxy statement/prospectus is dated [                    ], and is first being mailed to EEP unitholders on or about [            ].

ENBRIDGE ENERGY PARTNERS, L.P.

5400 Westheimer Court

Houston, Texas 77056

NOTICE OF SPECIAL MEETING OF UNITHOLDERS

To the Unitholders of Enbridge Energy Partners, L.P.:

Notice is hereby given that a special meeting of unitholders of Enbridge Energy Partners, L.P., a Delaware limited partnership, which is referred to as “EEP”, will be held on [            ], [            ] at [            ], local time, at 5400 Westheimer Court, Houston, Texas 77056, solely for the following purposes:

These items of business, including the Merger Agreement and the proposed Merger, are described in detail in the accompanying proxy statement/prospectus.

A special committee composed of independent members of the board of directors of the GP Delegate, which is referred to as the “Special Committee”, the board of directors of the GP Delegate, which is referred to as the “GP Delegate Board”, and the board of directors of the General Partner, which is referred to as the “GP Board”, each have, acting in good faith, determined that the Merger is fair and reasonable to EEP, including the holders of the outstanding units of EEP (other than Enbridge and its affiliates), have approved the Merger Agreement and the Merger and recommend that the EEP unitholders vote FOR the proposal to approve the Merger Agreement, and the GP Delegate Board and the GP Board each recommend that EEP unitholders vote FOR the adjournment of the special meeting from time to time if necessary to solicit additional proxies in favor of such approval.

Only EEP unitholders of record as of the close of business on [                    ] are entitled to notice of the special meeting and to vote at the special meeting or at any adjournment or postponement thereof. A list of EEP unitholders entitled to vote at the special meeting will be available in EEP’s offices located at 5400 Westheimer Court, Houston, Texas 77056, during regular business hours for a period of ten days before the special meeting, and at the place of the special meeting during the meeting.

YOUR VOTE IS VERY IMPORTANT!

Approval of the Merger Agreement by the holders of the EEP units (other than the Class F units of EEP, the “Outstanding EEP units”) is a condition to the consummation of the Merger and requires the affirmative vote of (1) the holders of at least 66 ²⁄₃% of the Outstanding EEP units, and (2) the holders of a majority of the outstanding Class A common units (other than any Class A common units held by Enbridge and its affiliates) and the outstanding i-units (other than i-units voted at the direction of Enbridge and its affiliates), voting together as a single class, in each case entitled to vote on such matter at the special meeting or any adjournment or postponement thereof. Therefore, your vote is very important. Your failure to vote your EEP units will have the same effect as a vote against the approval of the Merger Agreement. WHETHER OR NOT YOU EXPECT TO ATTEND THE SPECIAL MEETING IN PERSON, WE URGE YOU TO SUBMIT YOUR PROXY AS PROMPTLY AS POSSIBLE (1) THROUGH THE INTERNET, (2) BY TELEPHONE OR (3) BY MARKING, SIGNING AND DATING THE ENCLOSED PROXY CARD AND RETURNING IT IN THE POSTAGE-PAID ENVELOPE PROVIDED. You may revoke your proxy or change your vote at any

time by 11:59 p.m., Eastern Time, on the day before the special meeting. If your EEP units are held in the name of a bank, broker, nominee, trust company or other fiduciary, please follow the instructions on the voting instruction card furnished to you by them.

We urge you to carefully read the accompanying proxy statement/prospectus, including all documents incorporated by reference into it, and its annexes before voting your EEP units at the special meeting or submitting your voting instructions by proxy.

IF YOU PLAN TO ATTEND THE SPECIAL MEETING:

Please note that space limitations make it necessary to limit attendance to EEP unitholders. Admission to the special meeting will be on a first-come, first-served basis. Registration will begin at [            ] a.m., and seating will begin at [                ]. EEP unitholders will be asked to present valid picture identification, such as a driver’s license or passport. EEP unitholders holding Class A common units in brokerage accounts will also need to bring a copy of the voting instruction card that they receive from their broker or other nominee in connection with the special meeting or a brokerage statement reflecting unit ownership as of the record date. Cameras, recording devices and other electronic devices will not be permitted at the special meeting.

By order of the board of directors,

Jeffrey A. Connelly

Chairman of the Board of Directors

Enbridge Energy Company, Inc., as the general

partner of Enbridge Energy Partners, L.P.

Houston, Texas

[            ]

ADDITIONAL INFORMATION

This proxy statement/prospectus incorporates important business and financial information about Enbridge and EEP from other documents that Enbridge and EEP have filed with the U.S. Securities and Exchange Commission, which is referred to as the “SEC”, and that are contained in or incorporated by reference herein. For a listing of documents incorporated by reference herein, please see the section titled “Where You Can Find More Information” beginning on page [        ] of this proxy statement/prospectus. This information is available for you to review at the SEC’s public reference room located at 100 F Street, N.E., Room 1580, Washington, DC 20549, and through the SEC’s website at www.sec.gov.

You will also be able to obtain copies of documents filed by Enbridge with the SEC from Enbridge’s website at https://www.enbridge.com/ under the “Investment Center” link and then under the heading “Reports and SEC Filings” or copies of documents filed by EEP with the SEC by accessing EEP’s website at https://www.enbridgepartners.com/ under the “Investor Relations” link, and then under the heading “Financial Information”. The information contained on either of Enbridge’s or EEP’s respective websites is not incorporated into this proxy statement/prospectus and is not a part of this proxy statement/prospectus.

You may request copies of this proxy statement/prospectus and any of the documents incorporated by reference herein or other information concerning Enbridge or EEP, without charge, upon written or oral request to the applicable company’s principal executive offices. The respective addresses and telephone numbers of such principal executive offices are listed below.

In addition, if you have questions about the Merger or the special meeting, need additional copies of this proxy statement/prospectus or need to obtain proxy cards or other information related to the proxy solicitation, you may contact D.F. King & Co., Inc., EEP’s proxy solicitor, at the address and telephone numbers listed below. You will not be charged for any of these documents that you request.

D.F. King & Co., Inc.

48 Wall Street, 22nd Floor

New York, NY 10005

Banks and Brokers call: (212) 269-5550

All others call toll-free: (800) 549-6746

Email: Enbridge@dfking.com

To obtain timely delivery of these documents prior to the special meeting, holders of EEP units must request the information no later than [            ] (which is five business days before the date of the special meeting) in order to receive them before the special meeting.

ABOUT THIS PROXY STATEMENT/PROSPECTUS

This proxy statement/prospectus, which forms part of a registration statement on Form S-4 filed with the SEC by Enbridge (File No. 333-[            ]), constitutes a prospectus of Enbridge under Section 5 of the Securities Act of 1933, as amended (the “Securities Act”), with respect to the Enbridge common shares to be issued to holders of Class A common units pursuant to the Merger Agreement.

This proxy statement/prospectus also constitutes a notice of meeting and a proxy statement of EEP under Section 14(a) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), with respect to the special meeting of EEP unitholders, which is referred to as the “special meeting”, at which EEP unitholders will be asked to consider and vote on, among other matters, a proposal to approve the Merger Agreement.

We are responsible for the information contained in, and incorporated by reference into, this proxy statement/prospectus. We have not authorized anyone to give you any other information, and we take no responsibility for any other information that others may give you. You should bear in mind that although the information contained in, or incorporated by reference into, this proxy statement/prospectus is intended to be accurate as of the date on the front of such documents, such information may also be amended, supplemented or updated by the subsequent filing of additional documents deemed by law to be or otherwise incorporated by reference into this proxy statement/prospectus. Enbridge’s and EEP’s business, financial condition, results of operations and prospects may have changed since those dates.

This proxy statement/prospectus does not constitute an offer to sell, or a solicitation of an offer to buy, any securities, or the solicitation of a proxy, in any jurisdiction in which it is unlawful to make any such offer or solicitation.

Enbridge and EEP have both contributed to the information contained in this proxy statement/prospectus. The information concerning Enbridge contained in, or incorporated by reference into, this proxy statement/prospectus has been provided by Enbridge, and information concerning EEP contained in, or incorporated by reference into, this proxy statement/prospectus has been provided by EEP.

Unless otherwise specified, currency amounts referenced in this proxy statement/prospectus are in U.S. dollars.

CURRENCY EXCHANGE RATE DATA

The following table shows, for the years and dates indicated, certain information regarding the Canadian dollar/U.S. dollar exchange rate. The information is based on the daily exchange rate as reported by the Bank of Canada. Such exchange rate on October 2, 2018 was C$1.2817 = US$1.00.

FREQUENTLY USED TERMS

This proxy statement/prospectus generally does not use technical defined terms, but a few frequently used terms may be helpful for you to have in mind at the outset. Unless otherwise specified or if the context so requires, the following terms have the meanings set forth below for purposes of this proxy statement/prospectus:

“Canadian Tax Act” refers to the Income Tax Act (Canada), including the regulations promulgated thereunder, as amended from time to time.

“Class A common units” refers to the Class A common units representing limited partner interests in EEP.

“Class B common units” refers to the Class B common units representing limited partner interests in EEP. All outstanding Class B common units are held by the General Partner and have similar rights to the Class A common units, except with respect to certain allocations of taxable income. Class B common units are not publicly traded.

“Class E units” refers to the Class E units representing limited partner interests in EEP, all of which are held by the General Partner. There is no established public trading market for the Class E units.

“Class F units” refers to the Class F units representing limited partner interests in EEP, all of which are held by the General Partner. There is no established public trading market for the Class F units.

“Closing Date” refers to the date on which the Merger is completed.

“EEP” refers to Enbridge Energy Partners, L.P., a publicly-traded Delaware limited partnership.

“EEP Partnership Agreement” refers to the Eighth Amended and Restated Agreement of Limited Partnership of EEP, dated as of April 27, 2017, as amended.

“EEP unitholders” refers to holders of any EEP unit.

“EEP units” refers to the Class A common units, the Class B common units, the Class E units, the Class F units and the i-units of EEP.

“Effective Time” refers to the time on the Closing Date at which the Merger becomes effective as specified in the certificate of merger of EEP and Merger Sub to be filed with the Secretary of State of the State of Delaware.

“Enbridge” refers to Enbridge Inc., a Canadian corporation.

“Enbridge shareholders” refers to the holders of Enbridge common shares.

“Exchange Ratio” refers to 0.335 of a validly issued, fully paid and non-assessable Enbridge common share for each Class A common unit.

“Excluded Units” refers to Class A common units owned by Enbridge, the General Partner, Merger Sub or any other direct or indirect wholly owned subsidiary of Enbridge and Class A common units owned by the General Partner, the GP Delegate or EEP or any direct or indirect wholly owned subsidiary of EEP, and in each case not held on behalf of third parties.

“General Partner” refers to Enbridge Energy Company, Inc., a Delaware corporation and the general partner of EEP.

“GP Delegate” or “EEQ” refers to Enbridge Energy Management, L.L.C., a Delaware limited liability company and the delegate of the General Partner.

“i-unit” refers to the i-units representing limited partner interests of EEP. All i-units are owned by the GP Delegate and the i-units are not publicly traded.

“Majority of the Minority Vote” refers to the approval of the Merger Agreement by the holders of a majority of the outstanding Class A common units (other than Class A common units held by Enbridge and its affiliates) and the outstanding i-units (other than i-units voted at the direction of Enbridge and its affiliates), entitled to vote on such matter at the special meeting or any adjournment or postponement thereof, voting together as a single class.

“Merger” refers to the proposed merger of Merger Sub with and into EEP, pursuant to which EEP will survive the merger as an indirect wholly owned subsidiary of Enbridge.

“Merger Agreement” refers to the Agreement and Plan of Merger, dated as of September 17, 2018, entered into by and among EEP, the General Partner, the GP Delegate, Enbridge, Enbridge (U.S.) Inc., Merger Sub and, solely for purposes of Article I, Article II and Article XI therein, Enbridge US Holdings Inc.

“Merger Consideration” refers to the conversion of each issued and outstanding Class A common unit immediately prior to the Effective Time (other than the Excluded Units) into the right to receive 0.335 of a validly issued, fully paid and non-assessable Enbridge common share.

“Merger Sub” refers to Winter Acquisition Sub II, LLC, a Delaware limited liability company and an indirect wholly owned subsidiary of Enbridge.

“Midcoast Transaction” refers to the sale by Enbridge (U.S.) Inc., an indirect subsidiary of Enbridge, of Midcoast Operating, L.P. and its subsidiaries (collectively, “Midcoast”) to AL Midcoast Holdings, LLC for cash proceeds of approximately US$1.1 billion less deposits and other customary closing items, as disclosed in Enbridge’s Current Report on Form 8-K, filed with the SEC on August 1, 2018.

“Outstanding EEP units” refers to the EEP units, excluding the Class F units of EEP. Holders of Outstanding EEP units are entitled to vote at the special meeting.

“Record Date” refers to the close of business in New York, New York on [                    ].

“special meeting” refers to the special meeting of the holders of outstanding EEP units to be held on [                    ].

“Treaty” refers to the Canada-United States Income Tax Convention (1980).

“Unaffiliated EEP Unitholders” refers to the holders of Outstanding EEP units, other than Enbridge and its affiliates.

TABLE OF CONTENTS

-i-

-ii-

-iii-

-iv-

-v-

QUESTIONS AND ANSWERS

The following section provides brief answers to certain questions that you may have regarding the Merger Agreement and the proposed Merger. Please note that this section does not address all issues that may be important to you as a holder of EEP units. Accordingly, you should carefully read this entire proxy statement/prospectus, including each of the annexes, and the documents that have been incorporated by reference into this proxy statement/prospectus. Please read the section titled “Where You Can Find More Information” beginning on page [        ].

The Merger will become effective at the Effective Time.

1

The GP Delegate Board and the GP Board each recommend that you vote:

For a discussion of each proposal, see the sections titled “The Merger—Recommendation of the Special Committee” beginning on page [        ], “The Merger—Recommendation of the GP Delegate Board” beginning on page [        ], “The Merger—Recommendation of the GP Board” beginning on page [        ] and “The Merger—Reasons for the Recommendation of the Special Committee” beginning on page [        ].

Pursuant to the terms of the Merger Agreement, Enbridge and certain of its subsidiaries, which as of October 2, 2018 beneficially owned approximately 148.3 million Outstanding EEP units (inclusive of the approximately 11.5 million i-units corresponding to the number of shares of the GP Delegate indirectly owned by Enbridge) representing approximately 32.9% of the Outstanding EEP units, have agreed that, at the special meeting and at any meeting of holders of listed shares of EEQ held for the purpose of determining how the i-units shall be voted, it will vote, or cause to be voted, to the extent permitted under the organizational documents of EEQ, any EEP units or listed shares of EEQ then owned beneficially or of record by it or any of its subsidiaries, in favor of the approval of the Merger Agreement.

ENBRIDGE SHAREHOLDERS ARE NOT BEING ASKED FOR A CONSENT OR PROXY AND ENBRIDGE SHAREHOLDERS ARE REQUESTED NOT TO SEND ENBRIDGE A CONSENT OR PROXY.

2

For any adjournment proposal, you may vote FOR, AGAINST or ABSTAIN. If you abstain, it will have the same effect as a vote against this proposal. Failure to submit your proxy and to attend the meeting will have no effect on the outcome of any vote to adjourn the special meeting if a quorum is not present. If a quorum is present, it will have the same effect as a vote against any adjournment proposal. In addition, if your EEP units are held in the name of a bank, broker, nominee, trust company or other fiduciary, your bank, broker, nominee, trust company or other fiduciary will not be entitled to vote your EEP units on this proposal in the absence of specific instructions from you. These non-voted EEP units will not be counted as present for purposes of determining a quorum and will have no effect on the outcome of any vote of the EEP limited partners to adjourn the special meeting unless a quorum is present.

If you sign your proxy card without indicating how you wish to vote, your shares will be voted FOR the approval of the Merger Agreement and FOR any adjournment proposal, and in accordance with the recommendations of the GP Delegate Board and the GP Board on any other matters properly brought before the meeting for a vote.

3

If the Exchange Ratio would result in an Unaffiliated EEP Unitholder being entitled to receive, after aggregating all fractional units which such holder would otherwise be entitled to receive in connection with the Merger, a fraction of an Enbridge common share rounding to three decimal places, such holder will receive a cash payment (without interest, rounded down to the nearest cent) in lieu of such fractional Enbridge common share in an amount equal to the product obtained by multiplying (1) the amount of the fractional share interest in an Enbridge common share to which such holder would be entitled rounding to three decimal places and (2) an amount equal to the average of the volume-weighted average price per share of Enbridge common shares on the NYSE (as reported by Bloomberg L.P., or, if not reported therein, in another authoritative source mutually selected by Enbridge and EEP) on the trading day immediately prior to the Effective Time for ten trading days ending on the fifth full business day immediately prior to the Closing Date. For additional information regarding exchange procedures, please read “The Merger Agreement—Exchange Procedures” beginning on page [        ].

The Special Committee, the GP Delegate Board and the GP Board considered the benefits of the Merger Agreement, the Merger and the related transactions as well as the associated risks and, acting in good faith, unanimously (1) determined that the Merger Agreement and the transactions contemplated thereby,

4

including the Merger, are fair and reasonable to EEP, including the Unaffiliated EEP Unitholders, and (2) 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. The Special Committee recommended that the GP Delegate Board approve the Merger Agreement and the transactions contemplated thereby, including the Merger. The GP Delegate Board recommended that the GP Board approve the Merger Agreement and the transactions contemplated thereby, including the Merger. The GP Board directed that the Merger Agreement be submitted to the limited partners of EEP for their approval. Each of the GP Delegate Board and the GP Board recommends that the limited partners of EEP approve the Merger Agreement and the Merger.

If your EEP units are held by your bank, broker, nominee, trust company or other fiduciary, see below.

If your EEP units are held by your bank, broker, nominee, trust company or other fiduciary, often referred to as held in “street name”, please contact your bank, broker, nominee, trust company or other fiduciary to determine whether you will be able to vote by telephone or electronically.

5

If you choose either of these two methods, you must submit your notice of revocation or your new proxy card to the Corporate Secretary of the GP Delegate, at 5400 Westheimer Court, Houston, Texas 77056. You also may submit a later-dated proxy using the telephone or Internet voting procedures on the proxy card. 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., Eastern Time, on the day before the special meeting.

Finally, you may attend the special meeting and vote in person. Simply attending the special meeting, without voting in person, will not revoke your proxy. If your EEP units are held in street name and you have instructed a bank, broker, nominee, trust company or other fiduciary to vote your EEP units, you must follow the directions received from your bank, broker, nominee, trust company or other fiduciary to change your vote or to vote at the special meeting.

Please do not send in your EEP unit certificates now.

6

7

A Non-Canadian Resident Holder will not be subject to tax under the Canadian Tax Act on any capital gain realized on a disposition of Enbridge 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” beginning on page [        ] for a more complete discussion of the expected Canadian federal income tax consequences of owning and disposing of Enbridge common shares received in the Merger.

D.F. King & Co., Inc.

48 Wall Street, 22nd Floor

New York, NY 10005

Banks and Brokers call: (212) 269-5550

All others call toll-free: (800) 549-6746

Email: Enbridge@dfking.com

8

9

10

11

12

13

14

15

16

17

18

19

SELECTED HISTORICAL CONSOLIDATED FINANCIAL DATA OF ENBRIDGE

The following table sets forth the selected historical consolidated financial data of Enbridge as of and for the periods indicated. The selected historical consolidated financial data as of and for the years ended December 31, 2017, 2016, 2015, 2014 and 2013 were derived from Enbridge’s audited consolidated financial statements included in its annual reports on Form 10-K. The selected historical consolidated financial data as of June 30, 2018 and 2017 and for the six months ended June 30, 2018 and 2017 were derived from the unaudited consolidated interim financial statements of Enbridge included in its quarterly reports on Form 10-Q.

The information set forth below is not necessarily indicative of future results and should be read together with the other information contained in Enbridge’s Annual Report on Form 10-K for the fiscal year ended December 31, 2017 and its Quarterly Report on Form 10-Q for the quarter ended June 30, 2018, including the sections titled “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and the consolidated financial statements and related notes therein. See the section titled “Where You Can Find More Information” beginning on page [        ].

20

2018—Midcoast Operating, L.P. impairment, Line 10 impairment and other impairment

2017—The combination of Enbridge and Spectra Energy Corp (“Spectra Energy”) through a stock-for-stock merger transaction that closed on February 27, 2017, acquisition of public interest in Midcoast Energy Partners, L.P., the income tax benefit due to the enactment of the Tax Cuts and Jobs Act by the United States in December 2017 and other impairment

2016—Sandpiper Project impairment, gain on disposition of South Prairie Region assets, Tupper Plants acquisition and other impairment

2015—Goodwill impairment

21

SELECTED HISTORICAL CONSOLIDATED FINANCIAL DATA OF EEP

The following table sets forth the selected historical consolidated financial data of EEP as of and for the periods indicated. The selected historical consolidated financial data as of and for the years ended December 31, 2017, 2016, 2015, 2014 and 2013 were derived from EEP’s audited consolidated financial statements included in its annual reports on Form 10-K. The selected historical consolidated financial data as of June 30, 2018 and 2017 and for the six months ended June 30, 2018 and 2017 were derived from the unaudited consolidated interim financial statements of EEP included in its quarterly reports on Form 10-Q.

The information set forth below is not necessarily indicative of future results and should be read together with the other information contained in EEP’s Annual Report on Form 10-K for the fiscal year ended December 31, 2017 and its Quarterly Report on Form 10-Q for the quarter ended June 30, 2018, including the sections titled “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and the consolidated financial statements and related notes therein. See the section titled “Where You Can Find More Information” beginning on page [        ].

22

23

SELECTED UNAUDITED PRO FORMA CONDENSED CONSOLIDATED FINANCIAL INFORMATION

The following selected unaudited pro forma consolidated financial information is derived from the unaudited pro forma consolidated statements of earnings of Enbridge for the six months ended June 30, 2018 and the year ended December 31, 2017, which have been prepared to give effect to the Merger, the Midcoast Transaction and the Other Merger Transactions, as if such transactions were completed on January 1, 2017, and the unaudited pro forma consolidated balance sheet of Enbridge at June 30, 2018, which has been prepared to give effect to such transactions on June 30, 2018. The following selected unaudited pro forma consolidated financial information is for illustrative and informational purposes only and is not necessarily indicative of the results that might have occurred had such transactions taken place on January 1, 2017, for consolidated statements of earnings purposes, and June 30, 2018, for consolidated statements of financial position purposes, and is not intended to be a projection of future results. Future results may vary significantly from the results reflected because of various factors, including those discussed in the section titled “Risk Factors” beginning on page [        ] of this proxy statement/prospectus. The following selected unaudited pro forma consolidated financial information should be read in conjunction with the section titled “Unaudited Pro Forma Consolidated Financial Statements” and related notes beginning on page F-1 of this proxy statement/prospectus.

24

COMPARATIVE HISTORICAL AND UNAUDITED PRO FORMA PER SHARE AND PER UNIT FINANCIAL INFORMATION

Presented below are Enbridge’s and EEP’s historical and pro forma per share/unit data for the year ended December 31, 2017 and six months ended June 30, 2018. Except for the historical information for the year ended December 31, 2017, the information provided in the table below is unaudited. This information should be read together with the historical consolidated financial statements and related notes of Enbridge and EEP filed by each with the SEC, and incorporated by reference in this proxy statement/prospectus, and with the unaudited pro forma condensed consolidated financial statements included in the section titled “Unaudited Pro Forma Condensed Consolidated Financial Statements” beginning on page [        ].

The pro forma consolidated and pro forma consolidated equivalent per share information gives effect to the Merger, the Midcoast Transaction and the Other Merger Transactions as if such transactions had been completed as of the applicable date. Such pro forma information is presented for illustrative purposes only and is not necessarily indicative of the operating results or financial position that would have occurred if the Merger, the Midcoast Transaction or Other Merger Transactions had been completed as of the beginning of the periods presented, nor is it necessarily indicative of the future operating results or financial position of the consolidated company. The pro forma information, although helpful in illustrating the financial characteristics of the consolidated company under one set of assumptions, does not reflect the benefits of expected cost savings, opportunities to earn additional revenue, the impact of restructuring, or other factors that may result as a consequence of the Merger or other transactions and, accordingly, does not attempt to predict or suggest future results.

25

26

COMPARATIVE SHARE AND UNIT PRICES; DIVIDENDS AND DISTRIBUTIONS

Enbridge common shares are currently listed on the TSX and the NYSE under the symbol “ENB” and the Class A common units are currently listed on the NYSE under the symbol “EEP”. The table below sets forth, for the periods indicated, the per share high and low sales prices for Enbridge common shares as reported on the TSX and the NYSE and for the Class A common units as reported on the NYSE. Numbers have been rounded to the nearest whole cent.

The above table shows only historical data. You should obtain current market quotations for Enbridge common shares and Class A common units, as the market prices of such securities will fluctuate between the date of this proxy statement/prospectus and the date on which the Merger is completed, at times in between and thereafter. You can obtain these quotations from publicly-available sources.

27

Comparison of the Market Prices of Enbridge Common Shares and Class A Common Units and Implied Value of the Merger Consideration Payable for Each Class A Common Unit

The following table presents the closing price per share of Enbridge common shares on the TSX and the NYSE and of the Class A common units on the NYSE, in each case on (a) September 17, 2018, the last full trading day prior to the public announcement of the signing of the Merger Agreement, and (b) [            ], the last practicable trading day prior to the filing of this proxy statement/prospectus with the SEC. This table also shows the estimated implied value of the Merger Consideration payable for each Class A common unit, which was calculated by multiplying the closing price of Enbridge common shares on the NYSE on those dates by the Exchange Ratio of 0.335.

The market prices of Enbridge common shares and Class A common units have fluctuated since the date of the announcement of the Merger Agreement and will continue to fluctuate prior to, and in the case of Enbridge common shares, after, completion of the Merger. No assurance can be given concerning the market prices of Enbridge common shares or Class A common units before completion of the Merger or of Enbridge common shares after completion of the Merger. The Exchange Ratio is fixed in the Merger Agreement, but the market price of Enbridge common shares (and therefore the value of the Merger Consideration) when received by EEP unitholders after the Merger is completed could be greater than, less than or the same as shown in the table above. Accordingly, these comparisons may not provide meaningful information to EEP unitholders in determining whether to vote to approve the Merger Agreement and the Merger. EEP unitholders are encouraged to obtain current market quotations for Enbridge common shares and Class A common units and to review carefully the other information contained in this proxy statement/prospectus or incorporated by reference herein. For more information, see the section titled “Where You Can Find More Information” beginning on page [        ].

28

The table below sets forth the dividends declared per Enbridge common share and the distributions declared per Class A common unit for the periods indicated.

29

CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

This registration statement on Form S-4, of which this proxy statement/prospectus forms a part, and the documents to which Enbridge and EEP refer you in this registration statement, of which this proxy statement/prospectus forms a part, as well as oral statements made or to be made by Enbridge and EEP, contain both historical and forward-looking statements within the meaning of Section 27A of the Securities Act and Section 21E of the Exchange Act, and forward-looking information within the meaning of Canadian securities laws (collectively, “forward-looking statements”). Forward-looking statements are typically identified by words such as “anticipate”, “expect”, “project”, “estimate”, “forecast”, “plan”, “intend”, “target”, “believe”, “likely” and similar words suggesting future outcomes or statements regarding an outlook. Forward-looking information or statements included in, or incorporated by reference into, this proxy statement/prospectus include, but are not limited to, statements with respect to the following: the Merger; the Midcoast Transaction; each of the Other Merger Transactions; expected earnings before interest, income taxes and depreciation and amortization (“EBITDA”); expected earnings/(loss); expected earnings/(loss) per share; expected future cash flows; expected performance of the Liquids Pipelines, Gas Transmission and Midstream, Gas Distribution, Green Power and Transmission, and Energy Services businesses; financial strength and flexibility; expectations on sources of liquidity and sufficiency of financial resources; expected costs related to announced projects and projects under construction; expected in-service dates for announced projects and projects under construction (including potentially competitive projects); expected capital expenditures; expected equity funding requirements for Enbridge’s commercially secured growth capital; expected future growth and expansion opportunities; expectations about Enbridge’s joint venture partners’ ability to complete and finance projects under construction; expected closing of acquisitions and dispositions, including the Merger and the Other Merger Transactions; estimated future dividends; expected future actions of regulators; expected costs related to leak remediation and potential insurance recoveries; expectations regarding commodity prices; supply forecasts; expectations regarding the impact of the stock-for-stock merger transaction on February 27, 2017 between Enbridge and Spectra Energy, including Enbridge’s combined scale, financial flexibility, growth capital, future business prospects and performance; impact of the Canadian L3R Program on existing integrity programs; the sponsored vehicle strategy; dividend payout policy; dividend growth and dividend payout expectation; expectations on impact of hedging program; and expectations resulting from the successful execution of Enbridge’s 2018-2020 Strategic Plan.

Although the management of Enbridge and EEP believe that these forward-looking statements are reasonable based on the information available on the date such statements are made and processes used to prepare the information, such statements are not guarantees of future performance and may not prove to be accurate, and readers are cautioned against placing undue reliance on forward-looking statements. By their nature, these statements involve a variety of assumptions, known and unknown risks and uncertainties and other factors, which may cause actual results, future trends, levels of activity and achievements to differ materially from those matters expressed or implied by such statements. When considering forward-looking statements, readers and investors should keep in mind the risk factors and other cautionary statements described in the section titled “Risk Factors” beginning on page [        ]. Among the assumptions, risks and uncertainties that could cause actual results to differ from those described in forward-looking statements are the following:

30