Filed pursuant to 424(b)(3)
Registration No. 333-200594

BLACK CREEK INDUSTRIAL REIT IV INC.
SUPPLEMENT NO. 3 DATED SEPTEMBER 13, 2017
TO THE PROSPECTUS DATED JULY 3, 2017

        This prospectus supplement ("Supplement") is part of and should be read in conjunction with the prospectus of Black Creek Industrial REIT IV Inc., dated July 3, 2017 (the "Prospectus"), as supplemented by Supplement No. 1, dated August 9, 2017 ("Supplement No. 1") and Supplement No. 2, dated August 28, 2017 ("Supplement No. 2"). Unless otherwise defined herein, capitalized terms used in this Supplement shall have the same meanings as in the Prospectus.

        The purpose of this Supplement is as follows:

A.

To provide an update to the expected timing of the initial determination of an NAV per share of our common stock;



B.

To provide information regarding an authorized stock dividend;



C.

To update disclosure regarding the annual distribution fees paid on our Class T shares;



D.

To update disclosure regarding the organization and offering expense reimbursement payable to the Advisor;



E.

To update disclosure regarding the fixed component of the advisory fee;



F.

To update the section of the Prospectus titled "Investment Strategy, Objectives and Policies";



G.

To update disclosure regarding certain limitations on expense reimbursements to our Advisor;



H.

To update the labeling of one of the rows in the performance component calculation example;



I.

To update the section of the Prospectus titled "The Operating Partnership"; and



J.

To update Appendix B to the Prospectus.

A.    Update to the expected timing of the initial determination of an NAV per share of our common stock

        The board of directors has determined that it expects that the initial determination of an NAV per share of our common stock will occur as of a date no later than June 30, 2018. Therefore, any reference in the Prospectus, in Supplement No. 1 and in Supplement No. 2 to the expected timing of our initial determination of NAV per share of our common stock is hereby changed from "as of a date no later than December 31, 2017" to "as of a date no later than June 30, 2018."

B.    Dividend authorized by our board of directors

        The following information should be read in conjunction with the sections titled "Prospectus Summary—Distribution Policy" and "Description of Capital Stock—Distributions" on pages 30-31 and 211-213, respectively, of the Prospectus:

        Our board of directors has authorized the issuance of a stock dividend to all holders of Class T shares, whereby each Class T shareholder of record as of the close of business on September 29, 2017 will receive 50 Class W shares. This stock dividend will be issued following the close of business on September 29, 2017.

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C.    Update to disclosure regarding the annual distribution fees paid on our Class T shares

        1.     The last sentence of the second paragraph under the caption, "Class T Shares, Class W Shares and Class I Shares of Common Stock" in the "Prospectus Summary" section on page 2 of the Prospectus is hereby superseded and replaced with the following:

        Subject to FINRA limitation on underwriting compensation and certain other limitations, the ongoing distribution fees payable with respect to Class T shares and Class W shares sold in our primary offering is an annual amount equal to 1.0% of the NAV per Class T share and 0.5% per Class W share, respectively.

        2.     The dollar amount of "Annual Distribution Fees" for Class T shares in the table in the "Prospectus Summary—Class T Shares, Class W Shares and Class I Shares of Common Stock" and "Questions and Answers About This Offering—What are the Differences Among the Class T, Class W and Class I Shares of Common Stock Being Offered?" sections on pages 3 and 42, respectively, of the Prospectus, is hereby superseded and replaced with "$95."

D.    Update regarding Organization and Offering Expense Reimbursement to our Advisor

        The list of examples of organization and offering expenses in (i) the first sentence of the first paragraph under the caption "Organization and Offering Expense Reimbursement—the Advisor or its affiliates, including the Dealer Manager" in the "Prospectus Summary" and "Management Compensation" sections on pages 15 and 159, respectively, of the Prospectus, (ii) footnote (2) to the tables in the "Estimated Use of Proceeds" section on page 108, and (iii) the first sentence of the first paragraph under the caption "Other Compensation" in the section titled "Plan of Distribution—Underwriting Compensation" on page 270 of the Prospectus is revised to include "reimbursement of broker dealers for technology costs and expenses associated with the offering and costs and expenses associated with the facilitation of the marketing and ownership of our shares by their participating customers".

E.    Update regarding the fixed component of the advisory fee

        The following paragraph supersedes and replaces the second and third sentences in the first paragraph under the caption "Advisory Fee—Fixed Component and Expense Reimbursements—the Advisor" in the "Prospectus Summary" and "Management Compensation" sections on pages 16-17 and 160-161 of the Prospectus, respectively, and "Advisory Fee and Expense Reimbursements" in the "The Advisor and the Advisory Agreement—The Advisory Agreement" section on page 148 of the Prospectus:

        The fixed component of the advisory fee will consist of (i) a monthly fee of 1/12th of 0.80% of the aggregate cost (including debt, whether borrowed or assumed, and before non-cash reserves, depreciation and amortization expenses) of each real property asset within our portfolio (or our proportional interest therein with respect to real property held in joint ventures, co-ownership arrangements or real estate-related entities in which we own a majority economic interest or that we consolidate for financial reporting purposes in accordance with GAAP); provided, that the fixed component of the advisory fee with respect to each real property asset located outside the U.S. that we own, directly or indirectly, will be 1/12th of 1.20% of the aggregate cost (including debt, whether borrowed or assumed, and before non-cash reserves, depreciation and amortization expenses) of such real property asset, (ii) a monthly fee of one-twelfth of 0.80% of the aggregate cost or investment of any interest in any other real estate-related entity or any type of debt investment or other investment, and (iii) with respect to a disposition, a fee equal to 1.0% of the total consideration paid in connection with the disposition or gross market capitalization of the company upon the occurrence of a listing, calculated in accordance with the terms of the Advisory Agreement. The term "disposition" shall include (a) a sale of one or more assets, (b) a sale of one

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or more assets effectuated either directly or indirectly through the sale of any entity owning such assets, including, without limitation, us or the Operating Partnership, (c) a sale, merger, or other transaction in which the stockholders either receive, or have the option to receive, cash, securities redeemable for cash, and/or securities of a publicly traded company, or (d) a listing of our common stock on a national securities exchange or the receipt by our stockholders of securities that are listed on a national securities exchange in exchange for our common stock.

F.     Update to the section of the Prospectus titled "Investment Strategy, Objectives and Policies"

        1.     The following supersedes and replaces the last paragraph under the caption, "Borrowing Policies" on page 121 of the Prospectus:

        Our charter restricts us from obtaining loans from any of our directors, the Advisor, the Sponsor and any of our affiliates unless such loan is approved by a majority of our board of directors, including a majority of the independent directors, not otherwise interested in the transaction, as fair, competitive and commercially reasonable and no less favorable to us than comparable loans between unaffiliated parties.

        2.     The following supersedes and replaces the fourth bullet in the list under the caption, "Investment Limitations" on page 121 of the Prospectus:

•

Make or invest in mortgage loans that are subordinate to any lien or other indebtedness or equity interest of any of our directors, the Advisor, the Sponsor or any of their affiliates;

G.    Update regarding the certain limitations on expense reimbursements to the Advisor

        1.     The following supersedes and replaces the thirteenth paragraph under the caption, "Advisory Fee and Expense Reimbursements" in the "The Advisor and the Advisory Agreement—The Advisory Agreement" section on page 152 of the Prospectus:

        The Advisor must reimburse us at least annually for reimbursements paid to the Advisor in any year to the extent that such reimbursements to the Advisor cause our annual operating expenses to exceed the greater of (i) 2% of our average invested assets, which generally consists of the average of the aggregate book value of our assets before reserves for depreciation, bad debts and other non-cash reserves, computed by taking the average of such values as the end of each month during such period, or (ii) 25% of our net income, which is defined as our total revenues less total expenses for any given period excluding additions to reserves for depreciation, bad debts and other non-cash reserves, and excluding any gain from the sale of our assets. Such operating expenses will be calculated in accordance with GAAP (if it is still applicable under the then current accounting standards) and will include, but will not be limited to, items such as legal, accounting and auditing, advisory fees, transfer agent costs, D&O insurance, board of directors fees and related expenses, and expenses related to compliance with Sarbanes Oxley. Such operating expenses will not include (a) the expenses of raising capital such as organization and offering expenses, legal, audit, accounting, underwriting, brokerage, listing, registration and other fees, printing and other such expenses, and tax incurred in connection with the issuance, distribution, transfer and registration of our shares; (b) interest payments; (c) taxes; (d) non-cash expenditures such as depreciation, amortization and bad debt reserves; (e) incentive fees paid in compliance with the Statement of Policy; (f) acquisition fees, acquisition expenses, real estate commissions on the sale of property and other fees and expenses connected with the acquisition, disposition, management and ownership of real estate interests, mortgage loans or other property (including the costs of foreclosure, insurance premiums, legal services, maintenance, repair and improvement of property); and (g) distributions with respect to interests in the Operating Partnership.

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        2.     The following footnote supersedes and replaces footnote (4) to table in the "Management Compensation" section on page 169 of the Prospectus:

(4)

The Advisor must reimburse us at least annually for reimbursements paid to the Advisor in any year to the extent that such reimbursements to the Advisor cause our annual operating expenses to exceed the greater of (i) 2% of our average invested assets, which generally consists of the average of the aggregate book value of our assets before reserves for depreciation, bad debts and other non-cash reserves, computed by taking the average of such values as of the end of the month during such period, or (ii) 25% of our net income, which is defined as our total revenues less total expenses for any given period excluding additions to reserves for depreciation, bad debts and other non-cash reserves, and excluding an gain from the sale of our assets, unless the independent directors have determined that such excess expenses were justified based on unusual and non-recurring factors. The fixed and performance components of the advisory fee will count against the limit on total operating expenses. See "—The Advisory Agreement."

H.    Update to the performance component calculation example

        The parenthetical in row J of the table under the caption, "Performance Component Calculation Example" in the section titled "The Advisor and the Advisory Agreement—The Advisory Agreement" on page 153 of the Prospectus is hereby replaced with "(H multiplied by I)."

I.     Update to the section of the Prospectus titled "The Operating Partnership Agreement"

        1.     The following sentence supersedes and replaces the final sentence of the second paragraph under the caption, "General" on page 172 of the Prospectus:

        As of July 1, 2017, we owned a 99.9% limited partner interest in the Operating Partnership and a 0.1% general partner interest in the Operating Partnership and the Sponsor owned 100 Special Units as a limited partner.

        2.     The following paragraph supersedes and replaces the second paragraph under the caption, titled "Operations" on page 173 of the Prospectus:

        The Operating Partnership Agreement generally provides that, except as provided below with respect to the Special Units, the Operating Partnership will distribute cash flows from operating activities and, except as provided below, net sales proceeds from disposition of assets, to the partners of the Operating Partnership in accordance with their relative percentage interests, on at least a monthly basis (or at our election, more or less frequently), in amounts determined by us as general partner such that a holder of one OP Unit will generally receive the same amount of annual cash flow distributions from the Operating Partnership as the amount of annual distributions paid to the holder of one share of our common stock (before taking into account certain tax withholdings some states may require with respect to the OP Units).

J.     Update to Appendix B

        The subscription agreement included as Appendix B to the Prospectus is hereby superseded and replaced with Appendix A to this supplement.

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APPENDIX A: FORM OF SUBSCRIPTION AGREEMENT

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Filed pursuant to 424(b)(3) Registration No. 333-200594