Exhibit 99.1

FOR IMMEDIATE RELEASE

Plains All American Pipeline, L.P. and Plains GP Holdings Report Second-Quarter 2015 Results

(Houston — August 4, 2015) Plains All American Pipeline, L.P. (NYSE: PAA) and Plains GP Holdings (NYSE: PAGP) today reported second-quarter 2015 results.

Plains All American Pipeline, L.P.

Summary Financial Information (1) (unaudited)

(in millions, except per unit data)

(1)                                     PAA’s reported results include the impact of items that affect comparability between reporting periods. The impact of certain of these items is excluded from adjusted results.  See the section of this release entitled “Non-GAAP Financial Measures and Selected Items Impacting Comparability” and the tables attached hereto for information regarding certain selected items that PAA believes impact comparability of financial results between reporting periods, as well as for information regarding non-GAAP financial measures (such as adjusted EBITDA) and their reconciliation to the most directly comparable measures as reported in accordance with GAAP.

“PAA reported solid second quarter results, with adjusted EBITDA of $486 million, which was approximately $26 million above the mid-point of our quarterly guidance range,” said Greg L. Armstrong, Chairman and CEO of Plains All American. “PAA will pay a quarterly distribution of $0.695 per limited partner unit next week, which is the equivalent of $2.78 per unit on an annualized basis, while PAGP will pay a quarterly distribution of $0.227 per Class A share, or $0.908 per share on an annualized basis.  These distributions represent a 7.8% and 23.8% increase over comparative distributions paid in the same quarter of 2014, respectively.

333 Clay Street, Suite 1600          Houston, Texas 77002          713-646-4100 / 866-809-1291

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“Over the intermediate to long-term, we remain very constructive on the outlook for the North American crude oil industry.  Near term, we are cautious as high crude oil and refined product inventory levels will influence oilfield activity and crude oil production levels over the next six to twelve months and competition for the marginal barrel will intensify.  Additionally, our current forecast assumes that our All American pipeline in California will not be returned to service during the balance of 2015.”

Armstrong added, “Based on this outlook, we have reduced the midpoint of our full-year guidance for adjusted EBITDA by $50 million.  The resulting midpoint guidance of $2.275 billion remains in line with the full-year guidance range provided at the beginning of the year, albeit near the lower end of the initial range. Importantly, PAA remains well positioned to manage through industry down cycles and capitalize on attractive opportunities as it ended the second quarter of 2015 with approximately $3.1 billion of committed liquidity, a strong balance sheet and credit metrics that are consistent with our targeted levels.”

The following table summarizes selected PAA financial information by segment for the second quarter and first half of 2015:

Summary of Selected Financial Data by Segment (1) (unaudited)

(in millions)

(1)                                     PAA’s reported results include the impact of items that affect comparability between reporting periods. The impact of certain of these items is excluded from adjusted results. See the section of this release entitled “Non-GAAP Financial Measures and Selected Items Impacting Comparability” and the tables attached hereto for information regarding certain selected items that PAA believes impact comparability of financial results between reporting periods.

(2)                                     Certain of our non-GAAP financial measures may not be impacted by each of the selected items impacting comparability.

333 Clay Street, Suite 1600          Houston, Texas 77002          713-646-4100 / 866-809-1291

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Second-quarter 2015 Transportation adjusted segment profit increased 12% versus comparable 2014 results. This increase was driven by earnings from our 50% interest in the BridgeTex pipeline acquired in November 2014 and higher crude oil pipeline volumes associated with recently completed organic growth projects primarily within the Permian Basin and Eagle Ford producing regions.

Second-quarter 2015 Facilities adjusted segment profit increased by 6% over comparable 2014 results. This increase was primarily due to lower field operating costs associated with our NGL fractionation and Canadian natural gas processing activities.

Second-quarter 2015 Supply and Logistics adjusted segment profit exceeded the high end of our quarterly guidance range but decreased by 42% compared to 2014 results. This decrease was primarily driven by lower margins associated with less favorable crude oil market conditions.

Plains GP Holdings

PAGP’s sole assets are its ownership interest in PAA’s general partner and incentive distribution rights.  As the control entity of PAA, PAGP consolidates PAA’s results into its financial statements, which is reflected in the condensed consolidating balance sheet and income statement tables included at the end of this release.  Information regarding PAGP’s distributions is reflected below:

Conference Call

PAA and PAGP will hold a conference call on August 5, 2015 (see details below).  Prior to this conference call, PAA will furnish a current report on Form 8-K, which will include material in this news release as well as PAA’s financial and operational guidance for the third and fourth quarter and full year of 2015.  A copy of the Form 8-K will be available at www.plainsallamerican.com, where PAA and PAGP routinely post important information.

The PAA and PAGP conference call will be held at 11:00 a.m. EDT on Wednesday, August 5, 2015 to discuss the following items:

1.              PAA’s second-quarter 2015 performance;

2.              The status of major expansion projects;

3.              Capitalization and liquidity;

4.              Financial and operating guidance for the third and fourth quarter and full year of 2015; and

5.              PAA and PAGP’s outlook for the future.

333 Clay Street, Suite 1600          Houston, Texas 77002          713-646-4100 / 866-809-1291

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Conference Call Access Instructions

To access the Internet webcast of the conference call, please go to www.plainsallamerican.com, navigate to “Investor Relations,” select “PAA” or “PAGP,” then “News & Events,” and then “Quarterly Earnings.”  Following the live webcast, the call will be archived for a period of sixty (60) days on the website.

Alternatively, access to the live conference call is available by dialing toll free (800) 230-1059. International callers should dial (612) 234-9959.  No password is required.  The slide presentation accompanying the conference call will be available a few minutes prior to the call at the above referenced website.

Telephonic Replay Instructions

To listen to a telephonic replay of the conference call, please dial (800) 475-6701, or (320) 365-3844 for international callers, and enter replay access code 363940.  The replay will be available beginning Wednesday, August 5, 2015, at approximately 1:00 p.m. EDT and will continue until 11:59 a.m. EDT on September 5, 2015.

Non-GAAP Financial Measures and Selected Items Impacting Comparability

To supplement our financial information presented in accordance with GAAP, management uses additional measures that are known as “non-GAAP financial measures” (such as adjusted EBITDA and implied distributable cash flow (“DCF”)) in its evaluation of past performance and prospects for the future. Management believes that the presentation of such additional financial measures provides useful information to investors regarding our performance and results of operations because these measures, when used in conjunction with related GAAP financial measures, (i) provide additional information about our core operating performance and ability to generate and distribute cash flow, (ii) provide investors with the financial analytical framework upon which management bases financial, operational, compensation and planning decisions and (iii) present measurements that investors, rating agencies and debt holders have indicated are useful in assessing us and our results of operations. These measures may exclude, for example, (i) charges for obligations that are expected to be settled with the issuance of equity instruments, (ii) the mark-to-market of derivative instruments that are related to underlying activities in another period (or the reversal of such adjustments from a prior period), gains and losses on derivatives that are related to investing activities (such as the purchase of linefill) and inventory valuation adjustments, as applicable, (iii) long-term inventory costing adjustments, (iv) items that are not indicative of our core operating results and business outlook and/or (v) other items that we believe should be excluded in understanding our core operating performance. We have defined all such items as “Selected Items Impacting Comparability.”  We consider an understanding of these selected items impacting comparability to be material to the evaluation of our operating results and prospects.

Although we present selected items that we consider in evaluating our performance, you should also be aware that the items presented do not represent all items that affect comparability between the periods presented. Variations in our operating results are also caused by changes in volumes, prices, exchange rates, mechanical interruptions, acquisitions and numerous other factors. These types of variations are not separately identified in this release, but will be discussed, as applicable, in management’s discussion and analysis of operating results in our Quarterly Report on Form 10-Q.

333 Clay Street, Suite 1600          Houston, Texas 77002          713-646-4100 / 866-809-1291

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Adjusted EBITDA and other non-GAAP financial measures are reconciled to the most comparable measures as reported in accordance with GAAP for the periods presented in the tables attached to this release, and should be viewed in addition to, and not in lieu of, our Consolidated Financial Statements and notes thereto. In addition, PAA maintains on its website (www.plainsallamerican.com) a reconciliation of adjusted EBITDA and certain commonly used non-GAAP financial information to the most comparable GAAP measures. To access the information, investors should click on “PAA” under the “Investor Relations” tab on the home page, select the “Financial Information” tab and navigate to the “Non-GAAP Reconciliations” link.

Forward Looking Statements

Except for the historical information contained herein, the matters discussed in this release consist of forward-looking statements that involve certain risks and uncertainties that could cause actual results or outcomes to differ materially from results or outcomes anticipated in the forward-looking statements. These risks and uncertainties include, among other things, failure to implement or capitalize, or delays in implementing or capitalizing, on planned growth projects; declines in the volume of crude oil, refined product and NGL shipped, processed, purchased, stored, fractionated and/or gathered at or through the use of our facilities, whether due to declines in production from existing oil and gas reserves, failure to develop or slowdown in the development of additional oil and gas reserves, whether from reduced cash flow to fund drilling or the inability to access capital,  or other factors; unanticipated changes in crude oil market structure, grade differentials and volatility (or lack thereof); environmental liabilities or events that are not covered by an indemnity, insurance or existing reserves; fluctuations in refinery capacity in areas supplied by our mainlines and other factors affecting demand for various grades of crude oil, refined products and natural gas and resulting changes in pricing conditions or transportation throughput requirements; the effects of competition; the occurrence of a natural disaster, catastrophe, terrorist attack or other event, including attacks on our electronic and computer systems; tightened capital markets or other factors that increase our cost of capital or limit our ability to obtain debt or equity financing on satisfactory terms to fund additional acquisitions, expansion projects, working capital requirements and the repayment or refinancing of indebtedness; the currency exchange rate of the Canadian dollar; continued creditworthiness of, and performance by, our counterparties, including financial institutions and trading companies with which we do business; maintenance of our credit rating and ability to receive open credit from our suppliers and trade counterparties; weather interference with business operations or project construction, including the impact of extreme weather events or conditions; the availability of, and our ability to consummate, acquisition or combination opportunities; the successful integration and future performance of acquired assets or businesses and the risks associated with operating in lines of business that are distinct and separate from our historical operations; increased costs, or lack of availability, of insurance; non-utilization of our assets and facilities; the effectiveness of our risk management activities; shortages or cost increases of supplies, materials or labor; the impact of current and future laws, rulings, governmental regulations, accounting standards and statements and related interpretations; fluctuations in the debt and equity markets, including the price of our units at the time of vesting under our long-term incentive plans; risks related to the development and operation of our facilities, including our ability to satisfy our contractual obligations to our customers at our facilities; factors affecting demand for natural gas and natural gas storage services and rates; general economic, market or business conditions and the amplification of other risks caused by volatile financial markets, capital constraints and pervasive liquidity concerns; and other factors and uncertainties inherent in the transportation, storage, terminalling and marketing of crude oil and refined products, as well as in the storage of natural gas and the processing, transportation, fractionation, storage and marketing of natural gas liquids as discussed in the Partnerships’ filings with the Securities and Exchange Commission.

333 Clay Street, Suite 1600          Houston, Texas 77002          713-646-4100 / 866-809-1291

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Plains All American Pipeline, L.P. is a publicly traded master limited partnership that owns and operates midstream energy infrastructure and provides logistics services for crude oil, natural gas liquids (“NGL”), natural gas and refined products. PAA owns an extensive network of pipeline transportation, terminalling, storage and gathering assets in key crude oil and NGL producing basins and transportation corridors and at major market hubs in the United States and Canada. On average, PAA handles approximately 4.3 million barrels per day of crude oil and NGL on its pipelines. PAA is headquartered in Houston, Texas.

Plains GP Holdings is a publicly traded entity that owns an interest in the general partner and incentive distribution rights of Plains All American Pipeline, L.P., one of the largest energy infrastructure and logistics companies in North America. PAGP is headquartered in Houston, Texas.

333 Clay Street, Suite 1600          Houston, Texas 77002          713-646-4100 / 866-809-1291

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PLAINS ALL AMERICAN PIPELINE, L.P. AND SUBSIDIARIES

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS

(in millions, except per unit data)

ADJUSTED RESULTS

(in millions, except per unit data)

333 Clay Street, Suite 1600          Houston, Texas 77002          713-646-4100 / 866-809-1291

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PLAINS ALL AMERICAN PIPELINE, L.P. AND SUBSIDIARIES

CONDENSED CONSOLIDATED BALANCE SHEET DATA

(in millions)

DEBT CAPITALIZATION RATIOS

(in millions)

333 Clay Street, Suite 1600          Houston, Texas 77002          713-646-4100 / 866-809-1291

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PLAINS ALL AMERICAN PIPELINE, L.P. AND SUBSIDIARIES

SELECTED FINANCIAL DATA BY SEGMENT

(in millions)

(1)                                     Includes intersegment amounts.

(2)                                     Field operating costs and Segment general and administrative expenses exclude equity-indexed compensation expense, which is presented separately in the table above.

(3)                                     Segment general and administrative expenses reflect direct costs attributable to each segment and an allocation of other expenses to the segments. The proportional allocations by segment require judgment by management and are based on the business activities that exist during each period.

(4)                                     Certain of our non-GAAP financial measures may not be impacted by each of the selected items impacting comparability.

333 Clay Street, Suite 1600          Houston, Texas 77002          713-646-4100 / 866-809-1291

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PLAINS ALL AMERICAN PIPELINE, L.P. AND SUBSIDIARIES

OPERATING DATA (1)