Table of Contents The information in this preliminary prospectus supplement is not complete and may be changed. This preliminary prospectus supplement and the accompanying prospectus are not an offer to sell these securities, and we are not soliciting offers to buy these securities, in any jurisdiction where the offer or sale is not permitted. Filed Pursuant to Rule 424(b)(3) Registration No. 333-154677 Subject to Completion Preliminary Prospectus Supplement dated November 12, 2009 PROSPECTUS SUPPLEMENT (To prospectus dated October 23, 2008) $ % Notes due We are offering $ principal amount of % notes due . We will pay interest on the notes on and of each year, beginning , 2010. We may redeem the notes, in whole or in part, at any time prior to their maturity at the redemption price described in this prospectus supplement. The notes will be unsecured and will rank equally with all our other unsecured indebtedness from time to time outstanding. See “Risk Factors” beginning on page S-2 for a discussion of certain risks that you should consider in connection with an investment in the notes. Per Note Total Price to Public (1) % $ Underwriting Discounts and Commissions % $ Proceeds, Before Expenses % $ (1) plus accrued interest from , 2009 if settlement occurs after that date. Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of the notes or determined if this prospectus supplement or the accompanying prospectus is truthful or complete. Any representation to the contrary is a criminal offense. The notes will not be listed on any securities exchange. Currently, there is no public market for the notes. The underwriters expect to deliver the notes to purchasers through the book-entry delivery system of The Depository Trust Company for the benefit of its participants, including Euroclear and Clearstream, on or about , 2009. Joint-Book Running Managers BofA Merrill Lynch J.P. Morgan The date of this prospectus supplement is , 2009 Table of Contents TABLE OF CONTENTS Prospectus Supplement Page Where You Can Find More Information S-1 Risk Factors S-2 Raytheon Company S-4 Recent Developments S-5 Use of Proceeds S-5 Ratio of Earnings to Fixed Charges S-5 Capitalization S-6 Description of the Notes S-7 Certain U.S. Federal Income Tax Consequences S-11 Underwriting S-15 Legal Matters S-17 Experts S-17 Prospectus Page About This Prospectus 1 Where You Can Find More Information 1 Cautionary Note Regarding Forward-Looking Statements 2 Risk Factors 2 The Company 3 Use of Proceeds 3 Ratio of Earnings to Combined Fixed Charges 3 General Description of Securities That We May Sell 3 Description of Our Debt Securities 4 Description of Our Common Stock 12 Description of Our Preferred Stock 13 Description of Our Warrants 14 Plan of Distribution 15 Legal Matters 17 Experts 17 You should read this prospectus supplement along with the accompanying prospectus carefully before you invest in the notes. These documents contain or incorporate by reference important information you should consider before making your investment decision. This prospectus supplement contains specific information about the notes being offered and the accompanying prospectus contains a general description of the notes. This prospectus supplement may add, update or change information in the accompanying prospectus. You should rely only on the information provided or incorporated by reference in this prospectus supplement and the accompanying prospectus. We have not, and the underwriters have not, authorized anyone else to provide you with any different or additional information. You should not assume that the information contained in this prospectus supplement and the accompanying prospectus, as well as the information incorporated by reference, is accurate as of any date other than the date on the front cover of this prospectus supplement, or the date of such incorporated information. This prospectus supplement and the accompanying prospectus do not constitute an offer to sell, or the solicitation of an offer to buy, any securities other than the registered securities to which they relate, nor do this prospectus supplement and the accompanying prospectus constitute an offer to sell or a solicitation of an offer to buy these securities in any jurisdiction to any person to whom it is unlawful to make such offer or solicitation in such jurisdiction. Table of Contents References to “we,” “us,” “our,” “Raytheon” or the “Company” are to Raytheon Company and its consolidated subsidiaries or any part or division thereof, unless expressly indicated otherwise. References to “dollars” or “$” in this prospectus supplement and the accompanying prospectus are to U.S. dollars. Table of Contents WHERE YOU CAN FIND MORE INFORMATION We file annual, quarterly and current reports, proxy statements and other information with the SEC. You may read and copy any document that we file at the Public Reference Room of the SEC at 100 F Street, N.E., Washington, D.C. 20549. You may obtain information on the operation of the Public Reference Room by calling the SEC at 1-800-SEC-0330. In addition, the SEC maintains an internet site at www.sec.gov that contains reports, proxy statements and other information regarding registrants that file electronically, including Raytheon Company. Except as expressly set forth in the paragraph below, we are not incorporating the contents of the SEC website into this prospectus supplement. The SEC allows us to “incorporate by reference” into this prospectus supplement the information we file with it, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is an important part of this prospectus supplement, and information that we file later with the SEC will automatically update and supersede this information. We incorporate by reference into this prospectus supplement the documents listed below that we have filed with the SEC (File No. 1-3671) and any future filings made with the SEC by us under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended, until we sell all of the securities (other than filings or portions of filings that are furnished under applicable SEC rules rather than filed): • Annual Report on Form 10-K for the fiscal year ended December 31, 2008 filed on February 25, 2009; • Quarterly Report on Form 10-Q for the fiscal quarters ended March 29, 2009 filed on April 23, 2009, June 28, 2009 filed on July 23, 2009 and September 27, 2009 filed on October 22, 2009; and • Current Reports on Form 8-K filed on July 31 and October 29, 2009. You may request a copy of these filings at no cost, by writing or telephoning us at the following office: Office of the Corporate Secretary Raytheon Company 870 Winter Street Waltham, Massachusetts 02451 telephone (781) 522-3000. You may also find additional information about us, including the documents mentioned above, on our website at http://www.raytheon.com. The information included on or linked to this website or any website referred to in any document incorporated by reference into this prospectus supplement is not a part of this prospectus supplement. S-1 Table of Contents RISK FACTORS In addition to the information contained elsewhere or incorporated by reference into this prospectus supplement and the accompanying prospectus, you should carefully consider the risk factors identified below in evaluating an investment in the notes. Risks relating to our business. You should carefully consider the following risks, which are discussed under the section entitled “Risk Factors” in our Annual Report on Form 10-K for the year ended December 31, 2008: • our dependence on the U.S. Government for a substantial portion of our business and changes in government defense spending could have consequences on our financial position, results of operations and business; • the fact that our financial performance is dependent on our ability to perform our U.S. Government contracts which are subject to uncertain levels of funding and termination; • the fact that our international sales are a growing portion of our business; accordingly, we may increasingly become subject to the risks of doing business in foreign countries; • the fact that we may not be successful in obtaining the necessary licenses to conduct operations abroad, and Congress may prevent proposed sales to foreign governments; • the fact that competition within our markets may reduce our revenues and market share; • the dependence of our future success on our ability to develop new offerings and technologies for our current and future markets; • the fact that we enter into fixed-price and other contracts which could subject us to losses in the event that we experience cost growth that cannot be billed to customers; • the fact that our business could be adversely affected by a negative audit by the U.S. Government; • the fact that, as a U.S. Government contractor, we are subject to a number of procurement rules and regulations; • the dependence on component availability, subcontractor performance and our key suppliers to manufacture and deliver our products and services; • the fact that we use estimates in accounting for many of our programs and changes in our estimates could adversely affect our future financial results; • the fact that we use estimates and assumptions in accounting for our pension and other benefit plans, which are evaluated and updated on an annual basis. Changes in key estimates and assumptions,