WLKP Westlake Chemical Partners LP

On September 26, 2017, Westlake Chemical Partners LP (the “ Partnership ”) and Westlake Chemical Partners GP LLC (the “ General Partner ” and, together with the Partnership, the “ Partnership Parties ”) entered into an underwriting agreement (the “ Underwriting Agreement ”) with UBS Securities LLC and Citigroup Global Markets Inc., for themselves and as representatives of the other underwriters named therein (the “ Underwriters ”), providing for the offer and sale (the “ Offering ”) by the Partnership of 4,500,000 common units representing limited partner interests in the Partnership (“ Common Units ”), at a price to the public of $22.00 per Common Unit ($21.45 per Common Unit, net of underwriting discounts and commissions). Pursuant to the Underwriting Agreement, the Partnership also granted the Underwriters an option for a period of 30 days to purchase up to an additional 675,000 Common Units on the same terms. The Offering is expected to close on September 29, 2017.

The material terms of the Offering are described in a prospectus (the “ Prospectus ”), filed by the Partnership with the Securities and Exchange Commission (the “ Commission ”), pursuant to Rule 424(b)(5) under the Securities Act of 1933, as amended (the “ Securities Act ”). The Offering is registered with the Commission pursuant to a Registration Statement on Form S-3 (File No. 333-216617), which was declared effective by the Commission on March 24, 2017.

The Underwriting Agreement contains customary representations, warranties and agreements of the Partnership Parties, and customary conditions to closing, obligations of the parties and termination provisions. The Partnership Parties have agreed to indemnify the Underwriters against certain liabilities, including liabilities under the Securities Act, or to contribute to payments the Underwriters may be required to make because of any of those liabilities.

The Partnership will receive net proceeds (after deducting underwriting discounts and commissions, but before paying offering expenses payable by the Partnership) from the Offering of approximately $96.5 million. As described in the Prospectus, the Partnership will use the net proceeds of the sale of such Common Units, along with approximately $133.1 million of borrowing under its revolving credit facility, to fund its acquisition of additional interests in its partially owned subsidiary, Westlake Chemical OpCo LP.

As described in the Prospectus, affiliates of the Underwriters have in the past provided and may from time to time in the future provide commercial banking, investment banking and advisory services in the ordinary course of their business for the Partnership Parties and their respective affiliates, as applicable, for which they have received, and in the future may be entitled to receive, customary fees and reimbursement of expenses.

The foregoing description of the Underwriting Agreement is not complete and is qualified in its entirety by reference to the full text of the Underwriting Agreement, which is attached as Exhibit 1.1 to this report and incorporated by reference herein.