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

BLACK CREEK INDUSTRIAL REIT IV INC.
SUPPLEMENT NO. 5 DATED JUNE 15, 2018
TO THE PROSPECTUS DATED APRIL 30, 2018

        This prospectus supplement ("Supplement") is part of and should be read in conjunction with the prospectus of Black Creek Industrial REIT IV Inc., dated April 30, 2018 (the "Prospectus"), as supplemented by Supplement No. 1, dated May 15, 2018, Supplement No. 2, dated June 4, 2018, Supplement No. 3, dated June 11, 2018, and Supplement No. 4, dated June 13, 2018. 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 disclose the transaction price and offering price for each class of our common stock as of July 1, 2018;



B.

to disclose the calculation of our May 31, 2018 NAV per share for all share classes;



C.

to provide an update regarding the Operating Partnership Agreement and the Advisory Agreement";



D.

to provide an update to the section of the Prospectus titled "Risk Factors"; and



E.

to update the disclosure regarding our NAV calculation and valuation procedures.



A.

July 1, 2018 Transaction Price and Offering Price

        The transaction price and the offering price for each share class of our common stock for subscriptions accepted as of July 1, 2018 is as follows:

        The transaction price for each of our share classes is equal to such class's NAV per share as of May 31, 2018. A calculation of the NAV per share is set forth in Section B of this Supplement. The offering price of our common stock for each share class equals the transaction price of such class, plus applicable upfront selling commissions and dealer manager fees. Distribution reinvestment plan issuances as of June 29, 2018 and share redemptions as of June 30, 2018 will be made at the transaction price.

B.

May 31, 2018 NAV Per Share

        Our board of directors, including a majority of our independent directors, has adopted valuation procedures, as amended from time to time, that contain a comprehensive set of methodologies to be used in connection with the calculation of our NAV. Our most recent NAV per share for each share class, which is updated as of the last calendar day of each month, is posted on our website at www.blackcreekindustrialiv.com and is also available on our toll-free, automated telephone line at (888) 310-9352. Please refer to our valuation procedures in our Prospectus and Section D of this Supplement, for a more detailed description of our valuation procedures, including important disclosure regarding real property valuations provided by Altus Group U.S. Inc., or the "Independent Valuation Firm." All parties engaged by us in the calculation of our NAV, including the Advisor, are subject to

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the oversight of our board of directors. Generally, all of our real properties are appraised once each calendar year by third party appraisal firms in accordance with our valuation procedures and such appraisals are reviewed by our Independent Valuation Firm.

        As used below, "Fund Interests" means our outstanding shares of common stock, along with the partnership units in our operating partnership held by third parties (if any), and "Aggregate Fund NAV" means the NAV of all of the Fund Interests.

        The following table sets forth the components of total NAV as of May 31, 2018:

        The following table sets forth the NAV per Fund Interest as of May 31, 2018:

        The valuation for our real properties as of May 31, 2018 was provided by the Independent Valuation Firm in accordance with our valuation procedures and determined starting with the acquisition price of our real properties, which was adjusted based on subsequent events and assumptions used by the Independent Valuation Firm. Certain key assumptions that were used by our Independent Valuation Firm in the discounted cash flow analysis are set forth in the following table:

        In addition, the Independent Valuation Firm assumed a weighted-average holding period for our real properties of 10.6 years.

        A change in the rates used would impact the calculation of the value of our real properties. For example, assuming all other factors remain constant, the changes listed below would result in the following effects on the value of our real properties:

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C.

Update Regarding the Operating Partnership Agreement and the Advisory Agreement

        1)    All references throughout the Prospectus to the Operating Partnership Agreement mean the Fourth Amended and Restated Operating Partnership Agreement, dated as of June 13, 2018, as may be amended from time to time.

        2)    The following updates the description of the Advisory Agreement and the reimbursement to the Advisor of certain expenses in the sections of the Prospectus titled "Prospectus Summary—Compensation to the Advisor and its Affiliates," "Estimated Use of Proceeds," "The Advisor and the Advisory Agreement—The Advisory Agreement," "Management Compensation," and "Plan of Distribution—Other Compensation":

        We, the Operating Partnership, and the Advisor previously entered into the Fifth Amended and Restated Advisory Agreement, dated March 5, 2018, pursuant to which the Advisor performs certain duties and responsibilities as a fiduciary of us and our stockholders. The agreement has a term of one year, subject to renewal for an unlimited number of one-year periods. On June 13, 2018, we, the Operating Partnership and the Advisor entered into the Amended and Restated Advisory Agreement 2018, or the "Advisory Agreement", in order to renew the Advisory Agreement for an additional one-year term expiring June 13, 2019 and to amend certain of the terms related to the reimbursement of expenses.

        The Advisory Agreement amended the terms pursuant to which the Advisor will pay and be reimbursed for the payment of organization and offering expenses on our behalf. Per the terms of the Advisory Agreement, the Advisor has extended the duration of its prior agreement to advance all of our organization and offering expenses on our behalf, excluding upfront selling commissions, dealer manager fees and distribution fees, through December 31, 2018 (the Advisor had previously agreed to advance these expenses through June 30, 2018). We will reimburse the Advisor for all such advanced expenses ratably over the 60 months following December 31, 2018. Beginning January 1, 2019, we will reimburse the Advisor for any organization and offering expenses that it incurs on our behalf as and when incurred. After the termination of the primary offering and again after termination of the offering under our distribution reinvestment plan, the Advisor has agreed to reimburse us to the extent that the organization and offering expenses that we have incurred exceed 15% of our gross proceeds from the applicable offering. Any organization and offering expenses reimbursed by us which are deemed underwriting compensation will be subject to the 10% limit on underwriting compensation imposed by the Financial Industry Regulatory Authority.

        In addition, the Advisory Agreement amended the terms pursuant to which the Advisor will be reimbursed for acquisition expenses, such that until December 31, 2019, the Advisor will defer reimbursement of all or a portion of acquisition expenses incurred or paid on our behalf if, in a given month, the reimbursement of acquisition expenses to the Advisor would cause the NAV per share to be lower than the lesser of $10.00 or the NAV per share calculated for the prior month, which we refer to as a shortfall. If the reimbursement would result in a shortfall, then the Advisor will defer reimbursement of acquisition expenses in the amount necessary to prevent a shortfall for such month. The Advisor will be reimbursed for any such unreimbursed acquisition expenses ratably over the eighteen months following December 31, 2019.

        Following the termination of the Advisory Agreement, in addition to other amounts payable to the Advisor, the Advisor will be entitled to receive, subject to limitations on repayment set forth in our charter, all unpaid reimbursements of expenses, including any acquisition expenses that have not yet been reimbursed due to the Advisor's agreement to defer reimbursement as described above and any organization and offering expenses that have not been reimbursed due to the Advisor's agreement to advance such expenses as described above.

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D.

Update to the Section of the Prospectus Titled "Risk Factors"

        The following risk factors supersede and replace the last risk factor on each of pages 58 and 59, respectively, in the section of the Prospectus titled "Risk Factors—Risks Related to Investing in This Offering":

No rule or regulation requires that we calculate our NAV in a certain way, and our board of directors, including a majority of our independent directors, may adopt changes to the valuation procedures. In addition, because we do not include organization and offering expenses and acquisition expenses for which the Advisor has agreed to defer reimbursement in our calculation of NAV, our NAV will be higher during the period of the deferral than it would otherwise be but for the deferral by the Advisor and may decrease once such deferral ends.

        There are no existing rules or regulatory bodies that specifically govern the manner in which we calculate our NAV. As a result, it is important that you pay particular attention to the specific methodologies and assumptions we will use to calculate our NAV. Other public REITs may use different methodologies or assumptions to determine their NAV. In addition, each year our board of directors, including a majority of our independent directors, will review the appropriateness of our valuation procedures and may, at any time, adopt changes to the valuation procedures. For example, we do not currently include any enterprise value or real estate acquisition costs in our assets calculated for purposes of our NAV. If we acquire real property assets as a portfolio, we may pay a premium over the amount that we would pay for the assets individually. In addition, we will not include organization and offering expenses (other than selling commissions, dealer manager fees and distribution fees) incurred through December 31, 2018 in our calculation of NAV for periods through December 31, 2018, but rather will amortize them to expense on a straight-line basis over the five years following December 31, 2018. Beginning January 1, 2019, all organization and offering expenses (other than selling commissions, dealer manager fees and distribution fees, which will affect the NAV as indicated below) incurred, as well as those expenses incurred prior to January 1, 2019 which will be amortized, will reduce NAV as part of our estimated income and expense accruals. We have adopted this methodology due to the Advisor's agreement to advance all such organization and offering expenses through December 31, 2018 and to be reimbursed by us for such advanced organization and offering expenses ratably over the sixty months following December 31, 2018. Similarly, for NAV calculation purposes, any acquisition expenses incurred or paid through December 31, 2019 which have not been reimbursed to the Advisor will not reduce NAV for periods through December 31, 2019, but rather will be amortized to expense on a straight-line basis over the eighteen months following December 31, 2019. Beginning January 1, 2020, all acquisition expenses incurred, as well as those expenses incurred prior to January 1, 2020, which will be amortized, will reduce NAV as part of our estimated income and expense accruals. We have adopted this methodology due to the Advisor's agreement to defer reimbursement of all or a portion of acquisition expenses incurred or paid on our behalf if, in a given month, the reimbursement of acquisition expenses to the Advisor would cause the NAV per share to be lower than the lesser of $10.00 or the NAV per share calculated for the prior month, which we refer to as a shortfall. If the reimbursement would result in a shortfall, then the Advisor will defer reimbursement of acquisition expenses in the amount necessary to prevent a shortfall for such month. The Advisor will be reimbursed for any such unreimbursed acquisition expenses ratably over the eighteen months following December 31, 2019. Accordingly, during the period of the Advisor's deferral of the reimbursement of organization and offering expenses and acquisition expenses, our NAV will be higher than it would otherwise be but for the deferral, and may decrease once such deferral ends. Investors should consider this when determining to purchase shares of our common stock during the period of the deferral. As of May 31, 2018, the Advisor had incurred organization and offering expenses and acquisition expenses for which the Advisor had deferred reimbursement in an aggregate amount equal to $5.9 million. Our board of directors may change these or other aspects of our valuation procedures, which changes may have an adverse effect on our NAV and the price at which

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you may sell shares to us under our share redemption program. See our valuation procedures, filed as Exhibit 99.1 to this Current Report on Form 8-K, for more details regarding our valuation methodologies, assumptions and procedures.

New acquisitions may be valued for purposes of our NAV at less than what we pay for them, which would dilute our NAV and deferred reimbursements of acquisition expenses will dilute our NAV when repaid to the Advisor.

        Pursuant to our valuation procedures, the acquisition price of newly acquired properties will serve as our appraised value for the year of acquisition, and thereafter will be part of the rotating appraisal cycle such that they are appraised at least every calendar year. This is true whether the acquisition is funded with cash, equity or a combination thereof. However, the Independent Valuation Firm always has the ability to adjust property valuations for purposes of our NAV from the most recent appraised value. Similarly, if the Independent Valuation Firm believes that the purchase price for a recent acquisition does not reflect the current value of the property, the Independent Valuation Firm has the ability to adjust the valuation for purposes of our NAV downwards immediately after acquisition. Even if the Independent Valuation Firm does not adjust the valuation downwards immediately following the acquisition, when we obtain an appraisal on the property, it may not appraise at a value equal to the purchase price. Accordingly, the value of a new acquisition as established under our valuation procedures could be less than what we pay for it, which could negatively affect our NAV. Large portfolio acquisitions, in particular, may require a "portfolio premium" to be paid by us in order to be a competitive bidder, and this "portfolio premium" may not be taken into consideration in calculating our NAV. In addition, acquisition expenses we incur in connection with new acquisitions will negatively impact our NAV. The Advisor has agreed to defer reimbursement of all or a portion of acquisition expenses incurred or paid on our behalf if, in a given month, the reimbursement of acquisition expenses to the Advisor would cause the NAV per share to be lower than the lesser of $10.00 or the NAV per share calculated for the prior month, which we refer to as a shortfall. If the reimbursement would result in a shortfall, then the Advisor will defer reimbursement of acquisition expenses in the amount necessary to prevent a shortfall for such month. The Advisor will be reimbursed for any such unreimbursed acquisition expenses ratably over the eighteen months following December 31, 2019. Accordingly, during the period of the Advisor's deferral of the reimbursement of acquisition expenses, our NAV will be higher than it would otherwise be but for the deferral, and may decrease once such deferral ends. Investors should consider this when determining to purchase shares of our common stock during the period of the deferral. As of May 31, 2018, the Advisor had incurred acquisition expenses for which the Advisor had deferred reimbursement in an amount equal to $1.6 million. We may make acquisitions (with cash or equity) of any size without stockholder approval, and such acquisitions may be dilutive to our NAV.

E.

Update to the Disclosure Regarding Our NAV Calculation and Valuation Procedures

        1)    The following supersedes and replaces the section of the Prospectus titled "Prospectus Summary—NAV and NAV Per Share Calculation" on pages 6 - 7 of the Prospectus:

NAV and NAV per Share Calculation

        Our NAV per share will be calculated as of the last calendar day of each month for each of our outstanding classes of stock, and will be available generally within 15 calendar days after the end of the applicable month. Our NAV per share will be calculated by our Advisor or ALPS, a third-party valuation firm approved by our board of directors, including a majority of our independent directors. Our board of directors, including a majority of our independent directors, may replace ALPS, the Independent Valuation Firm, or any other party involved in our valuation procedures with another party, including our Advisor, if it is deemed appropriate to do so.

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        Each month, before taking into consideration accrued dividends or class-specific distribution fee accruals, any change in the Aggregate Fund NAV (whether an increase or decrease) from the prior month is allocated among each class of Fund Interest based on each class's relative percentage of the previous Aggregate Fund NAV. Changes in the Aggregate Fund NAV reflect factors including, but not limited to, unrealized/realized gains (losses) on the value of our real property portfolio, increases or decreases in real estate-related assets and liabilities, and monthly accruals for income and expenses (including accruals for performance based fees, if any, advisory fees and distribution fees) and distributions to investors.

        Our most significant source of income is property-level net operating income. We accrue revenues and expenses on a monthly basis based on actual leases and operating expenses in that month. For the first month following a property acquisition, we will calculate and accrue net operating income with respect to such property based on the performance of the property before the acquisition and the contractual arrangements in place at the time of the acquisition, as identified and reviewed through our due diligence and underwriting process in connection with the acquisition. For NAV calculation purposes, organization and offering costs (other than selling commissions, dealer manager fees and distribution fees) incurred prior to December 31, 2018 will not reduce NAV for periods through December 31, 2018, but rather will be amortized to expense on a straight-line basis over the five years following December 31, 2018. This is due to our Advisor's agreement to advance all such organization and offering costs through December 31, 2018 and to be reimbursed by us for such advanced organization and offering costs ratably over the five years following December 31, 2018. All organization and offering costs (other than selling commissions, dealer manager fees and distribution fees, which will affect the NAV as indicated below) incurred beginning January 1, 2019, will reduce NAV as part of our estimated income and expense accruals. In addition, until December 31, 2019, our Advisor has agreed to defer reimbursement of all or a portion of acquisition expenses incurred or paid on our behalf if, in a given month, the reimbursement of acquisition expenses to the Advisor would cause NAV per share to be lower than the lesser of $10.00 or the NAV per share calculated for the prior month, which we refer to as a shortfall. If the reimbursement would result in a shortfall, then our Advisor will defer reimbursement of acquisition expenses in the amount necessary to prevent a shortfall for such month. Our Advisor will be reimbursed for any such unreimbursed acquisition expenses ratably over the eighteen months following December 31, 2019. For NAV calculation purposes, any acquisition expenses incurred or paid prior to December 31, 2019 which have not been reimbursed to our Advisor pursuant to the deferral agreement described above will not reduce NAV for periods through December 31, 2019, but rather will be amortized to expense on a straight-line basis over the eighteen months following December 31, 2019. Beginning January 1, 2020, all acquisition expenses incurred will reduce NAV as part of our estimated income and expense accruals. On a periodic basis, our income and expense accruals are adjusted based on information derived from actual operating results.

        With the exceptions noted above in these valuation procedures, our liabilities are included as part of our NAV calculation and will be valued at fair value in accordance with GAAP. Our liabilities include, without limitation, property-level mortgages, accrued distributions, the fees payable to the Advisor and the Dealer Manager, accounts payable, accrued company-level operating expenses, any company or portfolio-level financing arrangements and other liabilities. Under GAAP, we record liabilities for distribution fees that we (i) currently owe our Dealer Manager under the terms of our dealer manager agreement and (ii) for an estimate that we may pay to our Dealer Manager in future periods. We do not deduct the liability for estimated future distribution fees in our calculation of NAV since we intend for our NAV to reflect our estimated value on the date that we determine our NAV. Accordingly, our estimated NAV at any given time should not include consideration of any estimated future distribution fees that may become payable after such date.

        Following the calculation and allocation of changes in the Aggregate Fund NAV as described above, NAV for each class is adjusted for accrued dividends and the ongoing distribution fees, to

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determine the monthly NAV. Upfront selling commissions and dealer manager fees will have no effect on the NAV of any class because they are effectively paid by the purchasers of shares in the primary offering at the time of purchase. The purchase price of such shares is equal to the transaction price, which generally will equal the most recently disclosed monthly NAV per share. We may offer shares at a price that we believe reflects the NAV per share of such stock more appropriately than the prior month's NAV per share in cases where we believe there has been a material change (positive or negative) to our NAV per share since the end of the prior month; however, such adjustments are anticipated to be infrequent.

        NAV per share for each class will be calculated by dividing such class's NAV at the end of each month by the number of shares outstanding for that class on such day. See "Net Asset Value Calculation and Valuation Procedures" for more details regarding our NAV per share calculations.

        2)    The following supersedes and replaces the section of the Prospectus titled "Net Asset Value Calculation and Valuation Procedures" on pages 188 - 194 of the Prospectus:

Overview

        Our board of directors, including a majority of our independent directors, has adopted valuation procedures, as amended from time to time, which contain a comprehensive set of methodologies to be used in connection with the calculation of our NAV. As a public company, we are required to issue financial statements generally based on historical cost in accordance with GAAP. To calculate our NAV for the purpose of establishing a purchase and redemption price for our shares, we have adopted valuation procedures, as explained below, which adjust the value of certain of our assets from historical cost to fair value. As a result, our NAV may differ from the amount reported as stockholders' equity on the face of our financial statements prepared in accordance with GAAP. The fair value of our assets and liabilities will be calculated for the purposes of determining our NAV per share, using widely accepted methodologies and, as appropriate, the GAAP principals within the FASB Accounting Standards Codification under Topic 820, Fair Value Measurements and Disclosures. However, our valuation procedures and our NAV are not subject to GAAP and will not be subject to independent audit. Furthermore, no rule or regulation requires that we calculate NAV in a certain way. Although we believe our NAV calculation methodologies are consistent with standard industry principles, there is no established practice among public REITs, whether listed or not, for calculating NAV in order to establish a purchase and redemption price. As a result, other public REITs may use different methodologies or assumptions to determine NAV.

Independent Valuation Firm

        With the approval of our board of directors, including a majority of our independent directors, we have engaged Altus Group U.S., Inc., a third-party valuation firm ("Altus Group" or the "Independent Valuation Firm"), to serve as our independent valuation firm with respect to the oversight of the annual appraisals of our real property assets, described below, and the monthly valuation of our real property portfolio. Altus Group is a multidisciplinary provider of independent, commercial real estate consulting and advisory services with multiple offices around the world, including in Canada, the U.K., Australia, the United States and Asia Pacific. Altus Group is engaged in the business of valuing commercial real estate properties and is not affiliated with us or the Advisor. The compensation we pay to the Independent Valuation Firm will not be based on the estimated values of our real estate assets. Our board of directors, including a majority of our independent directors, may replace the Independent Valuation Firm at any time. We will promptly disclose any changes to the identity or role of the Independent Valuation Firm in this prospectus and in reports we publicly file with the SEC.

        Altus Group will discharge its responsibilities in accordance with our real property valuation procedures described below and with the oversight of our board of directors. Our board of directors is

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not involved in the day-to-day valuation of the real property portfolio, but periodically receives and reviews such information about the valuation of the real property portfolio as it deems necessary to exercise its oversight responsibility. While our Independent Valuation Firm is responsible for providing our real property valuations, our Independent Valuation Firm is not responsible for nor prepares our monthly NAV.

        The Independent Valuation Firm will be engaged primarily to provide our monthly real property valuations and to help us manage the property appraisal process, but it may be engaged to provide additional services, including providing an independent valuation or appraisal of any of our other assets or liabilities (contingent or otherwise). Our Independent Valuation Firm may from time to time perform other commercial real estate and financial advisory services for our Advisor and its related parties, or in transactions related to the properties that are the subjects of the valuations being performed for us, or otherwise, so long as such other services do not adversely affect the independence of the applicable appraiser as certified in the applicable appraisal report or the independence of our Independent Valuation Firm.