8-K

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 8-K

CURRENT REPORT
Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): May 23, 2007

Tesoro Corporation

(Exact name of registrant as specified in its charter)

Delaware
(State or other jurisdiction
of incorporation) 1-3473
(Commission File Number) 95-0862768
(IRS Employer Identification No.)

300 Concord Plaza Drive
San Antonio, Texas
(Address of principal executive offices) 78216-6999
(Zip Code)

(210) 828-8484
(Registrant’s telephone number,
including area code)

Not Applicable
(Former name or former address, if
changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2.):

o      Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o      Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o      Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o      Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 8.01 Other Events.

On May 23, 2007, Tesoro Corporation (the “Company”) issued a press release (the “Press Release”) announcing that it had finalized the terms of its previously announced senior notes offering. The Company will issue $500 million in principal amount of 6.50% Senior Notes due 2017. The notes are unsecured. The Company anticipates that completion of the offering will occur on May 29, 2007 and intends to use the proceeds from the offering, together with cash on hand, to repay borrowings under the Company’s $700 million 364-day term loan. The 364-day term loan was used to finance, in part, the acquisition of certain assets from Shell Oil Products US. The 364-day term loan will be terminated upon repayment. The Press Release is filed as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated herein by reference.

Item 9.01 Financial Statements and Exhibits.

(c) Exhibits.

99.1 Press Release issued on May 23, 2007 by Tesoro Corporation.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934 the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Date: May 24, 2007

TESORO CORPORATION
By:	/s/ OTTO C. SCHWETHELM
	Otto C. Schwethelm
	Vice President, Finance and Treasurer

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Index to Exhibits

Exhibit Number	Description
99.1	Press Release issued on May 23, 2007 by Tesoro Corporation.

EX-99.1

Exhibit 99.1

FOR IMMEDIATE RELEASE

Contact:

Investors:
Scott Phipps, Manager, Investor Relations, (210) 283-2882

Media:
Natalie Silva, Manager, Public Relations, (210) 283-2729

TESORO CORPORATION ANNOUNCES PRICING OF

$500 MILLION 6.50% SENIOR NOTES

     SAN ANTONIO — May 23, 2007 — Tesoro Corporation (NYSE:TSO) today announced that it has finalized the terms of its previously announced senior notes offering. The Company will issue $500 million in principal amount of 6.50% Senior Notes due 2017. The notes are unsecured. The Company anticipates that consummation of the offering will occur on May 29, 2007 and intends to use the proceeds from the offering, together with cash on hand, to repay borrowings under the Company’s $700 million 364-day term loan. The 364-day term loan was used to finance, in part, the acquisition of certain assets from Shell Oil Products US. The 364-day term loan will be terminated upon repayment.

     The Notes will be issued in a private placement and are expected to be resold by the initial purchasers to qualified institutional buyers under Rule 144A and Regulation S under the Securities Act of 1933. The offer of the Notes will be made only by means of an offering memorandum to qualified investors and has not been registered under the Securities Act of 1933, and may not be offered or sold in the United States absent registration under the Securities Act of 1933 or an applicable exemption from the registration requirements of the Securities Act of 1933.

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     This press release shall not constitute an offer to sell or a solicitation of an offer to purchase any of these securities, and shall not constitute an offer, solicitation or sale in any state or jurisdiction in which such an offer, solicitation or sale would be unlawful.

     Tesoro Corporation, a Fortune 150 Company, is an independent refiner and marketer of petroleum products. Tesoro operates seven refineries in the western United States with a combined capacity of approximately 660,000 barrels per day. Tesoro’s retail-marketing system includes 881 branded retail stations, of which 464 are company owned retail stations.

     The foregoing statements regarding the Company’s intentions with respect to the contemplated offering and other transactions described above are forward-looking statements under the Private Securities Litigation Reform Act of 1995, and actual results could vary materially from the statements made. The Company’s ability to complete the offering and other transactions described above successfully is subject to various risks, many of which are outside of its control, including prevailing conditions in the capital markets and other risks and uncertainties as detailed from time to time in the reports filed by the Company with the Securities and Exchange Commission.

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