Exhibit 99.1

Spectra Energy Partners Reports Second Quarter 2011 Results

HOUSTON – Spectra Energy Partners, LP (NYSE: SEP) today reported second quarter 2011 net income of $37.6 million, or $0.36 per limited partner unit, compared with $33.2 million, or $0.38 per limited partner unit, for the second quarter 2010.

Increased net income resulted primarily from higher Gulfstream earnings due to the acquisition of an additional 24.5 percent interest in Gulfstream in the fourth quarter 2010, partially offset by lower revenues at Ozark and approximately $1.3 million in initial Big Sandy Pipeline, LLC acquisition and financing costs. Earnings per limited partner unit for the quarter reflect a higher number of weighted average units outstanding compared to the prior period.

Cash available for distribution was $35.4 million for the quarter, compared with $33.4 million in the second quarter 2010.

“Spectra Energy Partners delivered solid second quarter results, which supported our fifteenth consecutive quarterly cash distribution increase for investors,” said Greg Rizzo, president and chief executive officer. “The second quarter was also noteworthy as Spectra Energy Partners obtained its new investment grade credit ratings and completed its first-ever public debt offering, as well as a successful follow-on equity offering.”

“We ended the quarter in a strong financial position, which allowed us to fund the Big Sandy Pipeline acquisition on July 1, and at the same time, maintain ample liquidity to pursue future growth opportunities,” continued Rizzo.

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Results from Operations

Spectra Energy Partners reported operating income of $15.3 million for the second quarter 2011, compared with $19.9 million in the second quarter 2010. The decrease was primarily related to anticipated lower revenues at Ozark as well as increased expenses related to the acquisition of Big Sandy Pipeline, LLC.

Equity Investment in Gulfstream Natural Gas System, L.L.C. (Gulfstream)

Spectra Energy Partners recognized $15.4 million of earnings from its 49 percent interest in Gulfstream in the second quarter 2011, compared with $7.4 million from its 24.5 percent interest in the second quarter 2010.

For the quarter, Spectra Energy Partners’ share of Gulfstream’s cash available for distribution was $11.1 million, compared with $5.2 million in the second quarter 2010.

Equity Investment in Market Hub Partners (MHP)

Spectra Energy Partners recognized $11.4 million of earnings from its 50 percent interest in MHP in the second quarter 2011, compared with $9.8 million in the second quarter 2010. The increased earnings primarily reflect the final phase-in of expansion projects as well as lower operating expenses.

For the quarter, Spectra Energy Partners’ share of MHP’s cash available for distribution was $12.5 million, compared with $11.7 million in the second quarter 2010.

Interest Expense and Other

Interest expense for the quarter was $5.3 million, compared to $3.9 million for the prior-year quarter due to the $500 million of senior notes issued in June 2011.

Capital Expenditures and Equity Investments

During the quarter, Spectra Energy Partners invested $15.1 million in expansion and maintenance capital projects in the Gas Transportation and Storage segment, and an additional $7.0 million in expansion projects at MHP.

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Additional Information

The company will discuss its second quarter 2011 performance in greater detail during the analyst call which is scheduled for 9:00 a.m. CT today, August 4, 2011. The webcast can be accessed via the investor relations section of Spectra Energy Partners, LP’s web site or the conference call can be accessed by dialing (888) 252-3715 in the United States or (706) 634-8942 outside the United States. The Conference ID is 77962043.

Please call in five to ten minutes prior to the scheduled start time. A replay of the conference call will be available after 12:00 p.m. CT, August 4, 2011, until 5:00 p.m. CT, November 3, 2011, by dialing (800) 642-1687 with Conference ID 77962043. The international replay number is (706) 645-9291 with Conference ID 77962043. A replay and transcript also will be available by accessing the investor relations section of Spectra Energy Partners’ web site at http://www.spectraenergypartners.com.

Reconciliation of Non-GAAP Financial Measures

This press release includes certain financial measures, including cash available for distribution and adjusted Earnings Before Interest, Taxes, Depreciation and Amortization (EBITDA), that are non-GAAP (Generally Accepted Accounting Principles) financial measures, as defined under the rules of the Securities and Exchange Commission (SEC).

Spectra Energy Partners defines adjusted EBITDA as net income plus interest expense, income taxes, and depreciation and amortization, less equity in earnings of Gulfstream and MHP, interest income, and other income and expenses, net, which primarily includes non-cash AFUDC.

Spectra Energy Partners defines cash available for distribution as adjusted EBITDA plus cash available for distribution from Gulfstream and MHP and net preliminary project costs, less net cash paid for interest expense (income), net cash paid for income taxes and maintenance capital expenditures. Cash available for distribution does not reflect changes in working capital balances. Cash available for distribution for Gulfstream and MHP is defined on a basis consistent with Spectra Energy Partners.

This press release is accompanied by a reconciliation of these non-GAAP financial measures to their nearest GAAP financial measures. Management uses these financial measures because they are accepted financial indicators used by investors to compare company performance. In addition, management believes that these measures provide investors an enhanced perspective

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of the operating performance of the Partnership’s assets and the cash that the business is generating. Adjusted EBITDA and cash available for distribution are not presented as alternatives to net income or cash flow from operations. They should not be considered in isolation or as substitutes for a measure of performance prepared in accordance with United States GAAP.

Forward-Looking Statements

This document includes “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. Forward-looking statements are based on our beliefs and assumptions. These forward-looking statements are identified by terms and phrases such as: anticipate, believe, intend, estimate, expect, continue, should, could, may, plan, project, predict, will, potential, forecast, and similar expressions. Forward-looking statements involve risks and uncertainties that may cause actual results to be materially different from the results predicted. Factors that could cause actual results to differ materially from those indicated in any forward-looking statement include, but are not limited to: state and federal legislative and regulatory initiatives that affect cost and investment recovery, have an effect on rate structure, and affect the speed at and degree to which competition enters the natural gas industries; outcomes of litigation and regulatory investigations, proceedings or inquiries; weather and other natural phenomena, including the economic, operational and other effects of hurricanes and storms; the timing and extent of changes in interest rates; general economic conditions, including the risk of a prolonged economic slowdown or decline, or the risk of delay in a recovery, which can affect the long-term demand for natural gas and related services; potential effects arising from terrorist attacks and any consequential or other hostilities; changes in environmental, safety and other laws and regulations; results and costs of financing efforts, including the ability to obtain financing on favorable terms, which can be affected by various factors, including credit ratings and general market and economic conditions; increases in the cost of goods and services required to complete capital projects; growth in opportunities, including the timing and success of efforts to develop domestic pipeline, storage, gathering and other infrastructure projects and the effects of competition; the performance of natural gas transmission, storage and gathering facilities; the extent of success in connecting natural gas supplies to transmission and gathering systems and in connecting to expanding gas markets; the effect of accounting pronouncements issued periodically by accounting standard-setting bodies; conditions of the capital markets during the periods covered by the forward-looking statements; and the ability to successfully complete merger, acquisition or divestiture plans; regulatory or other limitations imposed as a result of a

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merger, acquisition or divestiture; and the success of the business following a merger, acquisition or divestiture. These factors, as well as additional factors that could affect our forward-looking statements, are described in our filings that we make with the Securities and Exchange Commission (SEC), which are available via the SEC’s Web site at www.sec.gov. In light of these risks, uncertainties and assumptions, the events described in the forward-looking statements might not occur or might occur to a different extent or at a different time than we have described. All forward-looking statements in this release are made as of the date hereof and we undertake no obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.

Spectra Energy Partners, LP (NYSE: SEP) is a Houston-based master limited partnership, formed by Spectra Energy Corp (NYSE: SE), that owns interests in natural gas transportation and storage assets in the United States, including more than 3,200 miles of transmission and gathering pipelines and approximately 57 billion cubic feet (Bcf) of natural gas storage. These assets are capable of transporting 3.5 Bcf of natural gas per day from growing supply areas to high-demand markets.

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Spectra Energy Partners, LP

Quarterly Highlights

June 2011

(Unaudited)

(In millions, except per-unit amounts)

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Spectra Energy Partners

Reconciliation of Non-GAAP “Adjusted EBITDA” and “Cash Available for Distribution”

(Unaudited)

(In millions)

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Gulfstream

Reconciliation of Non-GAAP “Adjusted EBITDA” and “Cash Available for Distribution”

(Unaudited)

(In millions)

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Market Hub

Reconciliation of Non-GAAP “Adjusted EBITDA” and “Cash Available for Distribution”

(Unaudited)

(In millions)

4 of 4