QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d)
OF THE SECURITIES EXCHANGE ACT OF 1934

Indicate by check mark whether the Registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that each Registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes [X]    No [  ]

Indicate by check mark whether the Registrant is an accelerated filer (as defined in Rule 12b-2 of the Exchange Act).    Yes [  ]    No [X]

Indicate the number of shares outstanding of each of the Registrant's classes of common stock, as of the latest practicable date (June 30, 2003):

All of the common stock of Wisconsin Gas Company is held by WICOR, Inc., a wholly-owned subsidiary of Wisconsin Energy Corporation.

Wisconsin Gas Company ("Wisconsin Gas" or the "Company"), a natural gas distribution public utility, is a Wisconsin corporation and wholly-owned, indirect subsidiary of Wisconsin Energy Corporation ("Wisconsin Energy").

Wisconsin Gas and Wisconsin Electric Power Company ("Wisconsin Electric"), another wholly-owned public utility subsidiary of Wisconsin Energy, have combined common functions and operate under the trade name of "We Energies".

The unaudited interim financial statements presented in this Form 10-Q have been prepared by Wisconsin Gas pursuant to the rules and regulations of the Securities and Exchange Commission. Certain information and note disclosures normally included in financial statements prepared in accordance with generally accepted accounting principles have been condensed or omitted pursuant to such rules and regulations. Wisconsin Gas' financial statements should be read in conjunction with the financial statements and notes thereto included in Wisconsin Gas' 2002 Annual Report on Form 10-K.

WISCONSIN GAS COMPANY
NOTES TO CONDENSED FINANCIAL STATEMENTS
(Unaudited)

The accompanying unaudited condensed financial statements for Wisconsin Gas Company should be read in conjunction with Item 8, Financial Statements and Supplementary Data, in Wisconsin Gas' 2002 Annual Report on Form 10-K. In the opinion of management, all adjustments, normal and recurring in nature, necessary to a fair statement of the results of operations, cash flows and financial position of Wisconsin Gas, have been included in the accompanying income statements, statements of cash flows and balance sheets. The results of operations for the three and six months ended June 30, 2003 are not necessarily indicative of the results which may be expected for the entire fiscal year 2003 because of seasonal and other factors.

Asset Retirement Obligations:   The Company adopted Statement of Financial Accounting Standards ("SFAS") No. 143, Accounting for Asset Retirement Obligations, effective January 1, 2003. Under SFAS 143, entities are required to record the fair value of a legal liability for an asset retirement obligation in the period in which it is incurred. When a new liability is recorded the entity capitalizes the costs of the liability by increasing the carrying amount of the related long-lived asset. The liability is accreted to its present value each period, and the capitalized cost is depreciated over the useful life of the related asset. At retirement, an entity settles the obligation for its recorded amount or incurs a gain or loss.

As of June 30, 2003, Wisconsin Gas has not identified any asset retirement obligations. However, the Company collects removal costs in rates for certain assets that do not have associated legal asset retirement obligations. As of June 30, 2003, the Company estimates that it has approximately $167 million related to removal costs recorded in Accumulated Depreciation.

Business Combinations and Goodwill: The Company accounts for goodwill and other intangibles under SFAS 142, Goodwill and Other Intangible Assets. Under SFAS 142, goodwill and other intangibles with indefinite lives are not subject to amortization. However, goodwill and other intangibles are subject to fair value-based rules for measuring impairment, and resulting write-downs, if any, are to be reflected in operating expense.

The Company assesses its fair value by considering future discounted cash flows. This analysis is supplemented with a review of fair value based on public company trading multiples and merger and acquisition transaction multiples for similar companies. This evaluation utilizes the information available under the circumstances, including reasonable and supportable assumptions and projections. The Company performs its annual impairment test as of August 31.

Financial Instruments with Characteristics of both Liabilities and Equity:   The Company adopted SFAS 150, Accounting for Certain Financial Instruments with Characteristics of both Liabilities and Equity, on July 1, 2003. SFAS 150, which was issued by the Financial Accounting Standards Board in May 2003, requires an issuer to classify outstanding freestanding financial instruments within its scope as a liability on its balance sheets even though the instruments have characteristics of equity. The Company identified no financial instruments that fall under the scope of SFAS 150.

Variable Interest Entities:   In January 2003, the Financial Accounting Standards Board issued Interpretation 46, Consolidation of Variable Interest Entities ("FIN 46"). This standard will require an enterprise that is the primary beneficiary of a variable interest entity to consolidate that entity. FIN 46 must be applied to any existing interests in variable interest entities beginning in the third quarter of 2003. The Company does not expect to consolidate any existing interests in unconsolidated entities as a result of FIN 46.

Comprehensive Income:   Comprehensive Income includes all changes in equity during a period except those resulting from investments by and distributions to owners. Wisconsin Gas had the following total Comprehensive Income during the six months ended June 30, 2003 and 2002:

Postemployment benefits:   Postemployment benefits provided to former or inactive employees are recognized when an event occurs. The estimated liability for such benefits has not changed significantly from the $1.6 million accrual recorded by the Company as of December 31, 2002.

Environmental Matters:   The Company periodically reviews its exposure for remediation costs as evidence becomes available indicating that its remediation liability has changed. Given current information, management believes that future costs in excess of the amounts accrued and/or disclosed on all presently known and quantifiable environmental contingencies will not be material to the Company's financial position or results of operations.

Cautionary Factors:   Certain statements contained herein are "Forward Looking Statements" within the meaning of the Private Securities Litigation Reform Act of 1995. Forward Looking Statements may be identified by reference to a future period or periods or by the use of forward looking terminology such as "may," "intends," "anticipates," "believes," "estimates," "expects," "forecasts," "objectives," "plans," "possible," "potential," "project" or similar terms or variations of these terms. Actual results may differ materially from those set forth in Forward Looking Statements as a result of certain risks and uncertainties, including but not limited to, changes in political and economic conditions, equity and bond market fluctuations, varying weather conditions, governmental regulation and supervision, as well as other risks and uncertainties detailed from time to time in filings with the Securities and Exchange Commission ("SEC") including factors described throughout this document and below in "Factors Affecting Results, Liquidity and Capital Resources".

Wisconsin Gas had a net loss of $3.4 million during the second quarter of 2003 compared with net income of $1.5 million during the second quarter of 2002, primarily reflecting a decline in operating income as a result of higher pension and benefit, bad debt, and depreciation and amortization expenses.

A comparison follows of the Company's operating revenues, gross margin and gas deliveries during the second quarter of 2003 with similar information for the second quarter of 2002 including favorable (better ("B")) or unfavorable (worse ("W")) variances. Gross margin is a better performance indicator than revenues because changes in the cost of gas sold flow through to revenue under gas cost recovery mechanisms. Due primarily to a significant increase in the delivered cost of natural gas between the comparative periods, gas operating revenues increased by $27.2 million or 28.8% offset by a $27.3 million or 47.2% increase in purchased gas costs.

For the three months ended June 30, 2003, gas margins decreased by $0.1 million or 0.3% when compared to the three months ended June 30, 2002 primarily reflecting a slight decline in gas deliveries to residential customers who contribute higher margins per therm than other customer classes. The following table compares Wisconsin Gas' gross margin and natural gas therm deliveries by customer class during the second quarter of 2003 with similar information for the second quarter of 2002.

Other Operation and Maintenance Expenses:   Other operation and maintenance expenses increased by $7.2 million or 34.0% during the second quarter of 2003 when compared with the second quarter of 2002. The increase was primarily attributable to $3.4 million of increased bad debt expense and to increased pension and benefits costs in the amount of $2.2 million.

Depreciation and Amortization:   Depreciation and amortization expenses increased by $1.2 million or 14.5% during the second three months of 2003 primarily due to a higher base of depreciable assets between the comparative periods.

Net income for the first six months of 2003 was $23.6 million, slightly lower than net income of $24.4 million for the first six months of 2002, primarily because an increase in gross margin due to favorable weather conditions during the first quarter of 2003 was offset by higher employee pension and benefit costs and an increase in bad debt expense during the first half of 2003.

A comparison follows of the Company's operating revenues, gross margin and gas deliveries during the first half of 2003 and the first half of 2002 including favorable (better ("B")) or unfavorable (worse ("W")) variances. Gross margin is a better performance indicator than revenues because changes in the cost of gas sold flow through to revenue under gas cost recovery mechanisms. Due primarily to a significant increase in the delivered cost of natural gas between the comparative periods, gas operating revenues increased by $155.1 million or 54.8% offset by a $144.0 million or 84.1% increase in purchased gas costs.

Gas margins increased $11.1 million or 10.0% between the comparative periods primarily due to a favorable weather-related increase in therm deliveries, especially to residential customers who are more weather sensitive and contribute higher margins per therm than other customer classes. As measured by heating degree days, the first half of 2003 was 15.3% colder than the first half of 2002 and 12.0% colder than normal. The following table compares Wisconsin Gas' gross margin and natural gas therm deliveries by customer class during the first half of 2003 with similar information for the first half of 2002.

Other Operation and Maintenance Expenses:   Other operation and maintenance expenses increased by $15.5 million or 36.2% during the first six months of 2003 when compared with the first six months of 2002. The increase was primarily attributable to $7.4 million of increased bad debt expense and to increased pension and benefits costs in the amount of $3.8 million.

The following summarizes Wisconsin Gas' cash flows during the first six months of 2003 and 2002:

Cash provided by operating activities decreased to $60.1 million during the first six months of 2003 compared with $88.5 million during the same period in 2002. This decline was due in large part to the effect on the cost of natural gas inventories due to higher per unit gas costs in 2003.

During the first six months of 2003, Wisconsin Gas had capital expenditures of $44.5 million, an increase of $27.8 million over the first six months of 2002. This increase reflects higher capital expenditures related to the Ixonia Lateral. In addition, Wisconsin Gas realized $12.0 million during the first half of 2002 from the sale of assets that did not recur during the first half of 2003.

During the six months ended June 30, 2003, Wisconsin Gas used $14.2 million to reduce short-term debt compared with $81.1 million during the first six months of 2002. This change can be attributed to the need for more capital as a result of increased construction costs and to increased costs related to gas in storage.

Cash requirements during the remaining six months of 2003 are expected to be met through a combination of internal sources of funds from operations, short-term borrowings and existing lines of credit supplemented, if necessary, through the sale of debt securities.

Depending upon market conditions and other factors including receipt of required regulatory approvals, Wisconsin Gas anticipates issuing $100 million of unsecured long-term debt during the fourth quarter of 2003.

The Company has access to outside capital markets and has been able to generate funds internally and externally to meet its capital requirements. Wisconsin Gas' ability to attract the necessary financial capital at reasonable terms is critical to the Company's overall strategic plan. The Company believes that it has adequate capacity to fund its operations for the foreseeable future through its borrowing arrangements and internally generated cash.

On June 30, 2003, Wisconsin Gas had approximately $200.0 million of available unused lines of bank back-up credit facilities. The Company had approximately $128.0 million of total short-term debt outstanding on such date.

Wisconsin Gas reviews its bank back-up credit facility needs on an ongoing basis and expects to be able to maintain adequate credit facilities to support its operations. The following table summarizes such facilities at June 30, 2003:

On June 25, 2003, Wisconsin Gas entered into an unsecured 364 day $200 million bank back-up credit facility to replace a $185 million credit facility that was scheduled to expire on December 10, 2003. The credit facility may be extended for an additional 364 days, subject to lender agreement.

The following table shows Wisconsin Gas' capitalization structure at June 30, 2003 and at December 31, 2002:

Access to capital markets at a reasonable cost is determined in large part by credit quality. The following table summarizes the current ratings of the debt securities of Wisconsin Gas by Standard & Poor's Ratings Services ("S&P"), Moody's Investors Service ("Moody's") and Fitch Ratings ("Fitch").

In February 2003, Moody's placed under review for possible downgrade Wisconsin Gas' long-term security rating and confirmed the commercial paper rating.

S&P and Fitch's current outlook for Wisconsin Gas is stable.

Wisconsin Gas believes these security ratings should provide a significant degree of flexibility in obtaining funds on competitive terms. However, these security ratings reflect the views of the rating agencies only. An explanation of the significance of these ratings may be obtained from each rating agency. Such ratings are not a recommendation to buy, sell or hold securities, but rather an indication of creditworthiness. Any rating can be revised upward or downward or withdrawn at any time by a rating

Capital requirements during the remainder of 2003 are expected to be principally for capital expenditures. Wisconsin Gas' 2003 annual capital expenditure budget is approximately $113 million.

Financial Instruments:   Wisconsin Gas is a party to various financial instruments with off-balance sheet risk as a part of its normal course of business, which may include, from time to time, financial guarantees and letters of credit which support construction projects, commodity contracts and other payment obligations. As of June 30, 2003, the Company's estimated maximum exposure under such agreements is zero.

Contractual Obligations/Commercial Commitments:   The Company's total contractual obligations and other commercial commitments as of June 30, 2003 decreased compared with December 31, 2002 due to customary periodic payments, along with reductions during the first six months of 2003 in obligations and commitments made in the ordinary course of business.

Limited Rate Adjustment Request:   Under the conditions of the Public Service Commission of Wisconsin's ("PSCW") Order authorizing Wisconsin Energy's acquisition of WICOR, Inc., the Company is authorized to seek rate reviews with the PSCW during a five-year rate restriction period that began January 1, 2001 limited to changes in revenue requirements as a result of:

• Governmental mandates;
• Abnormal levels of capital additions required to maintain or improve reliable electric service; and
• Major gas lateral projects associated with approved natural gas pipeline construction projects.

On July 2, 2003, Wisconsin Gas filed an application with the PSCW for $26.2 million (3.9%) of rate adjustments for anticipated 2004 revenue deficiencies associated with (1) increased costs linked to changes in Wisconsin's public benefits legislation, and (2) costs for construction of the Ixonia Lateral further described below. The Company anticipates an order from the PSCW on this request in early 2004.

Request for Deferral of Uncollectible Accounts Receivable:   Due to a combination of unusually high natural gas prices, the soft economy within its utility service territories, and limited governmental assistance available to low-income customers, the Company has seen a significant increase in uncollectible accounts receivable. Because of this, the Company sent a letter to the PSCW on July 23, 2003 requesting authority to defer for future rate recovery all bad debt expenses incurred during 2003 in excess of amounts included in current utility rates. The Company estimates such amount to be $7.2 million during 2003. In the letter, the Company stated its intention to suggest a mechanism for recovery of these costs, and to prevent such circumstances from recurring in the future. It is unknown when the PSCW will rule on this request.

Ixonia Lateral:   In April 2003, Wisconsin Gas started construction on the 35-mile Ixonia Lateral, which will connect the Wisconsin Gas distribution system to the Guardian Pipeline. The Ixonia Lateral is expected to provide substantial gas cost savings as well as critical additional pipeline capacity. Wisconsin Gas expects to complete and place the Ixonia Lateral in service in time to allow Wisconsin Gas to access its full contract capacity from Guardian Pipeline in the fourth quarter of 2003. In the event that the Ixonia Lateral is not completed prior to November 2003, Wisconsin Gas would incur additional operating costs for gas to be delivered into its service territory.

On August 24, 2001, Neighbors Standing United, a landowner group, and an individual landowner, filed petitions for review of the PSCW order dated July 25, 2001, which approved Wisconsin Gas' application to construct and operate the Ixonia Lateral. The Jefferson County Circuit Court on November 5, 2002 rendered a decision denying the petitions for review of the PSCW order and request for injunctive relief with one modification by the Court which narrowed the approved pipeline corridor from 800 to 200 feet. In December 2002, the landowner filed a notice of appeal of the Court decision to the Wisconsin Court of Appeals. On June 24, 2003, the Wisconsin Court of Appeals dismissed the landowner's appeal of the Circuit Court decision.

Power the Future - Port Washington:   Associated with construction of the Port Washington Generating Station under Wisconsin Energy's Power the Future strategy, Wisconsin Gas received a Certificate of Public Convenience and Necessity ("CPCN") from the PSCW in January 2003 authorizing construction of a 16.8 mile gas lateral that will connect the plant to the ANR Pipeline. It will also improve reliability for the natural gas distribution system in the area. The Company received a Chapter 30 wetland permit from the Wisconsin Department of Natural Resources ("WDNR") on July 3, 2003 approving construction of this lateral. The WDNR permitted construction of substantially the entire lateral consistent with the planned route previously approved by the PSCW, with certain exceptions. The Company has modified the planned route pursuant to the WDNR's request and will submit a request to the PSCW, if necessary, for re-approval of the modified rout e. Including the requested changes, the Company estimates the total cost of the project to be $39.5 million, subject to PSCW approval. Construction of the lateral is scheduled to begin in spring 2004 and to be completed by late 2004.

This report and other documents or oral presentations contain or may contain forward-looking statements made by or on behalf of Wisconsin Gas. Such statements are based upon management's current expectations and are subject to risks and uncertainties that could cause Wisconsin Gas' actual results to differ materially from those contemplated in the statements. Readers are cautioned not to place undue reliance on the forward-looking statements. When used in written documents or oral presentations, the terms "anticipate," "believe," "estimate," "expect," "forecast," "objective," "plan," "possible," "potential," "project" and similar expressions are intended to identify forward-looking statements. In addition to the assumptions and other factors referred to specifically in connection with such statements, factors that could cause Wisconsin Gas' actual results to differ materially from those contemplated in any forward-looking statements include, among others, the following:

• Factors affecting utility operations such as unusual weather conditions; catastrophic weather-related or terrorism-related damage; unplanned maintenance or repairs; unanticipated changes in gas supply or water supply costs or availability due to higher demand, shortages, transportation problems or other developments; nonperformance by natural gas suppliers under existing gas supply contracts; gas pipeline system constraints; unanticipated organizational structure or key personnel changes; collective bargaining agreements with union employees or work stoppages; inflation rates; or demographic and economic factors affecting utility service territories or operating environment.

• Regulatory factors such as unanticipated changes in rate-setting policies or procedures; unanticipated changes in regulatory accounting policies and practices; industry restructuring initiatives; distribution system and/or administration initiatives; recovery of costs of previous investments made under traditional regulation; recovery of costs associated with adoption of changed accounting standards; required changes in facilities or operations to reduce the risks or impacts of potential terrorist activities; required approvals for new construction; or changes in the regulations from the WDNR related to the siting approval process for new pipeline construction.

• Unexpected difficulties or unanticipated effects of the qualified five-year gas rate freeze ordered by the Public Service Commission of Wisconsin as a condition of its approval in 2000 of the merger of Wisconsin Energy Corporation and WICOR, Inc.

• The changing gas utility environment as market-based forces replace strict industry regulation and other competitors enter the gas markets resulting in increased wholesale and retail competition.

• Consolidation of the industry as a result of the combination and acquisition of utilities in the Midwest, nationally and globally.

• Changes in social attitudes regarding the utility industries.

• Customer business conditions including demand for their products or services and supply of labor and material used in creating their products and services.

• The cost and other effects of legal and administrative proceedings, settlements, investigations and claims, and changes in those matters.

• Factors affecting the availability or cost of capital such as changes in interest rates; the Company's capitalization structure; market perceptions of the utility industry or the Company; or security ratings.

• Federal, state or local legislative factors such as changes in tax laws or rates; changes in trade, monetary and fiscal policies, laws and regulations; electric and gas industry restructuring initiatives; or changes in environmental laws and regulations.

• Authoritative generally accepted accounting principle or policy changes from such standard setting bodies as the Financial Accounting Standards Board and the Securities and Exchange Commission.

• Unanticipated technological developments that result in competitive disadvantages and create the potential for impairment of existing assets.

• Other business or investment considerations that may be disclosed from time to time in Wisconsin Gas' Securities and Exchange Commission filings or in other publicly disseminated written documents.

Wisconsin Gas undertakes no obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.

*****

For certain other information which may impact Wisconsin Gas' future financial condition or results of operations, see Item 1, Financial Statements -- "Notes to Condensed Financial Statements," in Part I of this report as well as Item 1, Legal Proceedings, in Part II of this report.

For information concerning market risk exposures, see Item 7, Management's Discussion and Analysis of Financial Condition and Results of Operations -- "Factors Affecting Results, Liquidity and Capital Resources -- Market Risks and Other Significant Risks," in Part II of Wisconsin Gas' 2002 Annual Report on Form 10-K.

Disclosure Controls and Procedures:   The Company's management, with the participation of the Company's Chief Executive Officer and Chief Financial Officer, has evaluated the effectiveness of the Company's disclosure controls and procedures (as such term is defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934, as amended (the "Exchange Act")) as of the end of the period covered by this report. Based on such evaluation, the Company's Chief Executive Officer and Chief Financial Officer have concluded that, as of the end of such period, the Company's disclosure controls and procedures are effective in recording, processing, summarizing and reporting, on a timely basis, information required to be disclosed by the Company in the reports that it files or submits under the Exchange Act.

Internal Control Over Financial Reporting:   There have not been any changes in the Company's internal control over financial reporting (as such term is defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) during the fiscal quarter to which this report relates that have materially affected, or are reasonably likely to materially affect, the Company's internal control over financial reporting.

The following should be read in conjunction with Item 3, Legal Proceedings, in Part I of Wisconsin Gas' 2002 Annual Report on Form 10-K and Item 1, Legal Proceedings, in Part II of Wisconsin Gas' Quarterly Report on Form 10-Q for the period ended March 31, 2003.

In addition to those legal proceedings discussed in its reports to the SEC, the Company is currently, and from time to time, subject to claims and suits arising in the ordinary course of business. Although the results of such legal proceedings cannot be predicted with certainty, the Company's management, after consultation with legal counsel, believes that the ultimate resolution of these proceedings will not have a material adverse effect on the financial statements of the Company.

Columbia Propane Lawsuit:   In 1999, Wisconsin Gas was sued by Columbia Propane LP in the Circuit Court of Wood County, Wisconsin for an estimated $5 million in clean up costs related to a manufactured gas plant site in Marshfield, Wisconsin. The gas plant was owned and operated by People's Gas until 1960 when Wisconsin Gas acquired the assets of People's Gas subject to the terms of an Asset Purchase Agreement. In 1962, Wisconsin Gas sold the site to Columbia Propane. Columbia Propane asserted in the lawsuit that Wisconsin Gas stood in the shoes of People's Gas and was liable for environmental liabilities. Wisconsin Gas contested the liability and filed a motion for summary judgment contending that as a matter of law it was not liable for the clean up costs. The judge granted Wisconsin Gas' motion for summary judgment and dismissed the complaint, but on December 28, 2001, the Wisconsin Court of Appeals reversed the trial court and remanded the matter back for trial on the issue as to whether the parties intended tort liability to be assumed by Wisconsin Gas under the terms of the Asset Purchase Agreement. In April 2002, the Wisconsin Supreme Court granted a Petition for Review filed by Wisconsin Gas, and oral arguments were held on January 15, 2003. On May 13, 2003, the Wisconsin Supreme Court reversed the Court of Appeals' decision. The Supreme Court determined that the trial court correctly dismissed the lawsuit against Wisconsin Gas.

See Item 2, Management's Discussion and Analysis of Financial Condition and Results of Operations - "Factors Affecting Results, Liquidity and Capital Resources" in Part I of this report for information concerning Wisconsin Gas rate matters.

Gale E. Klappa, President of Wisconsin Energy Corporation, was elected President and Chief Executive Officer of Wisconsin Gas Company on July 31, 2003. Mr. Klappa succeeds Richard R. Grigg as President of Wisconsin Gas and assumes the title of Chief Executive Officer of Wisconsin Gas from Richard A. Abdoo.

The following Exhibits are filed with or incorporated by reference in this Form 10-Q report:

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 thereunto duly authorized.