Duke Energy : 424B5

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Filed pursuant to Rule 424(b)(5)

			Registration No. 333-213765-06
CALCULATION OF REGISTRATION FEE
	​		​
	​	Proposed	​
		Proposed	Amount of
		maximum	maximum
	Amount to be	offering price	aggregate	registration
Title of each class of securities to be registered	registered​	per unit	offering​ price	fee(1)
3.50% Senior Notes due 2029	$600,000,000​	99.748%	$598,488,000​	$72,536.75

1. The filing fee, calculated in accordance with Rule 457(r) under the Securities Act of 1933, as amended, has been transmitted to the Securities and Exchange Commission in connection with the securities offered by means of this prospectus supplement.

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Prospectus Supplement

(To Prospectus dated March 25, 2019)

$600,000,000

Piedmont Natural Gas Company, Inc.

3.50% Senior Notes due 2029

Piedmont Natural Gas Company, Inc. is offering $600,000,000 aggregate principal amount of 3.50% senior notes due 2029 (the "Notes"). The per annum interest rate on the Notes will be 3.50%. We will pay interest on the Notes semi-annually in arrears on June 1 and December 1 of each year, beginning on December 1, 2019. The Notes will mature as to principal on June 1, 2029. We may redeem the Notes at our option at any time and from time to time, in whole or in part, as described in this prospectus supplement under the caption "Description of the Notes-Optional Redemption." The Notes will not be entitled to the benefit of any sinking fund.

The Notes will be our direct, senior unsecured and unsubordinated obligations, ranking equally in right of payment with all of our existing and future senior unsecured indebtedness and be effectively subordinated (to the extent of underlying collateral) to any of our secured indebtedness now outstanding or that we may incur in the future.

The Notes are a new issue of securities with no established trading market. We do not intend to list the Notes on any securities exchange or include them in any automated quotation system. Please read the information provided under the caption "Description of the Notes" in this prospectus supplement and "Description of Debt Securities" in the accompanying prospectus for a more detailed description of the Notes.

Investing in the Notes involves risks. See "Risk Factors" on page S-7 of this prospectus supplement.

						Proceeds to
						Piedmont Natural
		Price to	Underwriting	Gas Company, Inc.
		Public(1)		Discount(2)		Before Expenses
Per Note	99.748%		0.650%	99.098%
Total Notes	$ 598,488,000		$ 3,900,000		$ 594,588,000

1. Plus accrued interest from May 24, 2019, if settlement occurs after that date.
2. The underwriters have agreed to make a payment to us in an amount equal to $1,200,000, including in respect of expenses incurred by us in connection with this offering. See "Underwriting (Conflicts of Interest)."

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus supplement or the accompanying prospectus. Any representation to the contrary is a criminal offense.

We expect the Notes to be ready for delivery only in book-entry form through the facilities of The Depository Trust Company for the accounts of its participants, including Clearstream Banking, S.A. and Euroclear Bank S.A./N.V., on or about May 24, 2019.

		Joint Book-Running Managers
BNP PARIBAS	Credit Suisse	SMBC Nikko	US Bancorp
		Co-Managers
BB&T Capital Markets		Loop Capital Markets	Regions Securities LLC
		Junior Co-Managers
Academy Securities		Drexel Hamilton			Mischler Financial Group, Inc.

The date of this prospectus supplement is May 21, 2019.

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You should rely only on the information contained in or incorporated by reference in this prospectus supplement, the accompanying prospectus and any free writing prospectus authorized by us. We have not, and the underwriters have not, authorized anyone to provide you with information that is different. If anyone provides you with different or inconsistent information, you should not rely on it. We are not, and the underwriters are not, making an offer to sell these securities in any jurisdiction where the offer is not permitted. You should not assume that the information contained in or incorporated by reference in this prospectus supplement, the accompanying prospectus or any free writing prospectus authorized by us is accurate as of any date other than the date of the document containing the information or such other date as may be specified therein. Our business, financial condition, liquidity, results of operations and prospects may have changed since those respective dates.

TABLE OF CONTENTS
Prospectus Supplement	Page
About this Prospectus Supplement	S-1
Prospectus Supplement Summary	S-3
Risk Factors	S-7
Cautionary Statement Regarding Forward-Looking Information	S-7
Use of Proceeds	S-9
Description of the Notes	S-10
Certain U.S. Federal Income Tax Considerations for Non-U.S. Holders	S-16
Underwriting (Conflicts of Interest)	S-19
Legal Matters	S-24
Where You Can Find More Information	S-25
Prospectus
About this Prospectus	1
Cautionary Statement Regarding Forward-Looking Statements	2
Risk Factors	3
About Piedmont	3
Use of Proceeds	4
Ratio of Earnings to Fixed Charges	4
Description of Debt Securities	4
Plan of Distribution	17
Legal Matters	18
Experts	18
Where You Can Find More Information	18
Incorporation by Reference	19

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ABOUT THIS PROSPECTUS SUPPLEMENT

This document is in two parts. The first part is this prospectus supplement, which describes the specific terms of this offering. The second part, the accompanying prospectus, gives more general information, some of which does not apply to this offering.

If the description of this offering varies between this prospectus supplement and the accompanying prospectus, you should rely on the information contained in or incorporated by reference in this prospectus supplement.

It is important for you to read and consider all information contained in or incorporated by reference in this prospectus supplement and the accompanying prospectus in making your investment decision. You should also read and consider the information contained in the documents to which we have referred you in "Where You Can Find More Information" in this prospectus supplement and the accompanying prospectus.

Unless we have indicated otherwise, or the context otherwise requires, references in this prospectus supplement and the accompanying prospectus to

"Piedmont," "we," "us" and "our" or similar terms are to Piedmont Natural Gas Company, Inc. and its subsidiaries. References in this prospectus supplement to "Debt Securities" are to debt securities issued under the Indenture (as defined under "Description of the Notes" below) and from time to time outstanding.

Notice to Prospective Investors in the European Economic Area

Neither this prospectus supplement nor the accompanying prospectus and any related free writing prospectus is a prospectus for the purposes of the Prospectus Directive (as defined below). This prospectus supplement, the accompanying prospectus and any related free writing prospectus have been prepared on the basis that any offer of the Notes in any Member State of the European Economic Area (the "EEA") which has implemented the Prospectus Directive (each, a "Relevant Member State") will only be made to a legal entity which is a qualified investor under the Prospectus Directive ("Qualified Investors"). Accordingly, any person making or intending to make an offer in that Relevant Member State of Notes which are the subject of the offering contemplated in this prospectus supplement, the accompanying prospectus and any related free writing prospectus may only do so with respect to Qualified Investors. Neither Piedmont nor the underwriters have authorized, nor do they authorize, the making of any offer of Notes other than to Qualified Investors. The expression "Prospectus Directive" means Directive 2003/71/EC (as amended or superseded), and includes any relevant implementing measure in the Relevant Member State.

Prohibition of Sales to EEA Retail Investors-The Notes are not intended to be offered, sold or otherwise made available to and should not be offered, sold or otherwise made available to any retail investor in the EEA. For these purposes, a retail investor means a person who is one (or more) of: (i) a retail client as defined in point (11) of Article 4(1) of Directive 2014/65/EU, as amended ("MiFID II"); or (ii) a customer within the meaning of Directive (EU) 2016/97, as amended or superseded (the "Insurance Distribution Directive"), where that customer would not qualify as a professional client as defined in point (10) of Article 4(1) of MiFID II; or (iii) not a qualified investor as defined in the Prospectus Directive. Consequently no key information document required by Regulation (EU) No 1286/2014, as amended (the "PRIIPs Regulation") for offering or selling the Notes or otherwise making them available to retail investors in the EEA has been prepared and therefore offering or selling the Notes or otherwise making them available to any retail investor in the EEA may be unlawful under the PRIIPs Regulation.

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Notice to Prospective Investors in the United Kingdom

The communication of this prospectus supplement, the accompanying prospectus, any related free writing prospectus, and any other document or materials relating to the issue of the Notes offered hereby is not being made, and such documents and/or materials have not been approved, by an authorized person for the purposes of section 21 of the United Kingdom's Financial Services and Markets Act 2000, as amended (the "FSMA"). Accordingly, such documents and/or materials are not being distributed to, and must not be passed on to, the general public in the United Kingdom. The communication of such documents and/or materials as a financial promotion is only being made to those persons in the United Kingdom who have professional experience in matters relating to investments and who fall within the definition of investment professionals (as defined in Article 19(5) of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2005, as amended (the "Financial Promotion Order")), or who fall within Article 49(2)(a) to (d) of the Financial Promotion Order, or who are any other persons to whom it may otherwise lawfully be made under the Financial Promotion Order (all such persons together being referred to as "relevant persons"). In the United Kingdom, the Notes offered hereby are only available to, and any investment or investment activity to which this prospectus supplement, the accompanying prospectus and any related free writing prospectus relates will be engaged in only with, relevant persons. Any person in the United Kingdom that is not a relevant person should not act or rely on this prospectus supplement, the accompanying prospectus or any related free writing prospectus or any of their contents.

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