UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

FORM 8-K

CURRENT REPORT

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

MGIC Investment Corporation

MGIC Plaza, 250 East Kilbourn Avenue
Milwaukee, Wisconsin 53202

(414) 347-6480

Table of Contents

Item 7. Financial Statements and Exhibits

     (c) Exhibits

Pursuant to General Instruction B.6 to Form 8-K, the Company’s July 14, 2004 press release is furnished as Exhibit 99 and is not filed.

Item 12. Results of Operations and Financial Condition

The Company issued a press release on July 14, 2004 announcing its results of operations for the quarter and six months ended June 30, 2004 and certain other information. The press release is furnished as Exhibit 99.

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.

INDEX TO EXHIBITS

Exhibit 99

MGIC Investment Corporation
Second Quarter Net Income of $154.5 Million

MILWAUKEE (July 14, 2004) — MGIC Investment Corporation (NYSE:MTG) today reported net income for the quarter ended June 30, 2004 of $154.5 million, compared with the $143.8 million for the same quarter a year ago. Diluted earnings per share were $1.56 for the quarter ending June 30, 2004, compared to $1.46 for the same quarter a year ago.

Net income for the first six months of 2004 was $284.6 million, compared with $284.9 million for the same period last year. For the first six months of 2004, diluted earnings per share was $2.87 compared with $2.87 for the same period last year.

Curt S. Culver, president and chief executive officer of MGIC Investment Corporation and Mortgage Guaranty Insurance Corporation (MGIC), said that the lack of growth of insurance in force has continued to negatively impact earned premiums. As a result, we expect earned premiums to be challenged for the balance of the year. However, we remain encouraged by the credit loss development.

Total revenues for the second quarter were $403.1 million, down 6.7 percent from $432.1 million in the second quarter of 2003. The decline in revenues resulted primarily from a 1.8 percent decrease in net premiums earned, to $331.1 million. Net premiums written for the quarter were $319.1 million, compared with $320.5 million in the second quarter last year.

New insurance written in the second quarter was $16.1 billion, compared to $25.4 billion in the second quarter of 2003. New insurance written for the quarter included $2.9 billion of bulk business compared with $6.6 billion in the same period last year. New insurance written in the first six months of 2004 was $29.1 billion versus $49.5 billion for the same period last year and includes $5.0 billion of bulk business versus $13.3 billion in the same period last year.

Persistency, or the percentage of insurance remaining inforce from one year prior, was 53.8 percent at June 30, 2004, compared with 47.1 percent at December 31, 2003, and 49.8 percent at June 30, 2003. As of June 30, 2004, MGIC’s primary insurance inforce was $180.4 billion, compared with $189.6 billion at December 31, 2003, and $193.6 billion at June 30, 2003. The book value of MGIC Investment Corporation’s investment portfolio was $5.4 billion at June 30, 2004, compared with $5.2 billion at December 31, 2003, and $5.0 billion at June 30, 2003.

At June 30, 2004, the percentage of loans that were delinquent, excluding bulk loans, was 3.58 percent, compared with 3.76 percent at December 31, 2003, and 3.38 percent at June 30, 2003. Including bulk loans, the percentage of loans that were delinquent at June 30, 2004 was 5.55 percent, compared to 5.57 percent at December 31, 2003, and 4.95 percent at June 30, 2003.

Losses incurred in the second quarter were $154.1 million, down from $173.1 million reported for the same period last year due primarily to a lower growth rate of the delinquency inventory. Underwriting expenses were $73.6 million in the second quarter, down from $80.1 million reported for the same period last year due to decreases in underwriting volumes.

About MGIC

MGIC (www.mgic.com), the principal subsidiary of MGIC Investment Corporation, is the nation’s leading provider of private mortgage insurance coverage with $180.4 billion primary insurance inforce covering 1.47 million mortgages as of June 30, 2004. MGIC serves 5,000 lenders with locations across the country and in Puerto Rico, helping families achieve homeownership sooner by making affordable low-down-payment mortgages a reality.

Webcast Details

As previously announced, MGIC Investment Corporation will hold a webcast today at 10 a.m. ET to allow securities analysts and shareholders the opportunity to hear management discuss the company’s quarterly results. The call is being webcast and can be accessed at the company’s website at www.mgic.com. The webcast is also being distributed over CCBN’s Investor Distribution Network to both institutional and individual investors. Investors can listen to the call through CCBN’s individual investor center at www.companyboardroom.com or by visiting any of the investor sites in CCBN’s Individual Investor Network. The webcast will be available for replay through August 14, 2004.

This press release, which includes certain additional statistical and other information, including non-GAAP financial information, is available on the Company’s website at www.mgic.com under “Investor — News and Financials — News Releases.”

Safe Harbor Statement

Forward-Looking Statements and Risk Factors:

The Company’s revenues and expenses could be affected by the risk factors discussed below. These factors may also cause actual results to differ materially from the results contemplated by forward looking statements that the Company may make. Forward looking statements consist of statements which relate to matters other than historical fact. Among others, statements that include words such as the Company “believes,” “anticipates” or “expects,” or words of similar import, are forward looking statements. The Company is not undertaking any obligation to update any forward looking statements it may make.

As the domestic economy deteriorates, more homeowners may default and the Company’s losses may increase.

Losses result from events that reduce a borrower’s ability to continue to make mortgage payments, such as unemployment, and whether the home of a borrower who defaults on his mortgage can be sold for an amount that will cover unpaid principal and interest and the expenses of the sale. Favorable economic conditions

generally reduce the likelihood that borrowers will lack sufficient income to pay their mortgages and also favorably affect the value of homes, thereby reducing and in some cases even eliminating a loss from a mortgage default. A deterioration in economic conditions generally increases the likelihood that borrowers will not have sufficient income to pay their mortgages and can also adversely affect housing values.

The mix of business the Company writes also affects the likelihood of losses occurring. In recent years, a greater percentage of the Company’s volume than in the past has included segments that the Company views as having a higher probability of claim, including loans with LTV ratios over 95%, FICO credit scores below 620 or limited underwriting, including limited borrower documentation. In response to lower national origination volume in 2004 compared to 2003, mortgage lenders may seek to maintain their own volume through a greater focus on lending to borrowers in segments that the Company views as having a higher probability of claim.

Approximately 8% of the Company’s risk in force written through the flow channel, and more than half of the Company’s risk in force written through the bulk channel, consists of ARMs. The Company believes that during a prolonged period of rising interest rates, claims on ARMs would be substantially higher than for fixed rate loans, although the performance of ARMs has not been tested in such an environment.

The performance of the servicing function on a mortgage loan, particularly a subprime loan, can affect the likelihood that the loan will default as well as the loss resulting from a default. The Company believes Select Portfolio Servicing f/k/a Fairbanks Capital Corp. (“Fairbanks”) is the servicer of approximately 1.2% of the loans insured by the Company and approximately 5.7% of the loans insured by the Company written through the bulk channel (a substantial number of which are subprime). The servicer ratings assigned to Fairbanks by Moody’s and S&P were downgraded to “below average” during the second quarter of 2003 due in part to concerns expressed by those rating agencies about Fairbanks’ regulatory compliance and operational controls. In the second quarter of 2004, these rating agencies raised Fairbanks’ service ratings to “average.”

Competition or changes in the Company’s relationships with its customers could reduce the Company’s revenues or increase its losses.

Competition for private mortgage insurance premiums occurs not only among private mortgage insurers but also with mortgage lenders through captive mortgage reinsurance transactions. In these transactions, a lender’s affiliate reinsures a portion of the insurance written by a private mortgage insurer on mortgages originated or serviced by the lender.

The level of competition within the private mortgage insurance industry has also increased as many large mortgage lenders have reduced the number of private mortgage insurers with whom they do business. At the same time, consolidation among mortgage lenders has increased the share of the mortgage lending market held by large lenders.

Our private mortgage insurance competitors include:

Assured Guaranty Limited f/k/a/ AGC Holdings Limited, a financial guaranty company whose mortgage insurance business is primarily reinsurance, has announced that it intends to write investment grade mortgage guaranty insurance on a direct basis.

If interest rates decline, house prices appreciate or mortgage insurance cancellation requirements change, the length of time that our policies remain in force could decline and result in declines in our revenue.

In each year, most of the Company’s premiums are from insurance that has been written in prior years. As a result, the length of time insurance remains in force (which is also generally referred to as persistency) is an important determinant of revenues. The factors affecting the length of time the Company’s insurance remains in force include:

During the 1990s, the Company’s year-end persistency ranged from a high of 87.4% at December 31, 1990 to a low of 68.1% at December 31, 1998. At June 30, 2004 persistency was at 53.8%, which was an improvement over the record low of 44.9% at September 30, 2003. Over the past several years, refinancing has become easier to accomplish and less costly for many consumers. Hence, even in an interest rate environment favorable to persistency improvement, the Company does not expect persistency will approach its December 31, 1990 level.

If the volume of low down payment home mortgage originations declines, the amount of insurance that the Company writes could decline which would reduce the Company’s revenues.

The factors that affect the volume of low down payment mortgage originations include:

In general, the majority of the underwriting profit (premium revenue minus losses) that a book of mortgage insurance generates occurs in the early years of the book, with the largest portion of the underwriting profit realized in the first year. Subsequent years of a book generally result in modest underwriting profit or underwriting losses. This pattern of results occurs because relatively few of the claims that a book will ultimately experience occur in the first few years of the book, when premium revenue is highest, while subsequent years are affected by declining premium revenues, as persistency decreases due to loan prepayments, and higher losses.

If all other things were equal, a decline in new insurance written in a year that followed a number of years of higher volume could result in a lower contribution to the mortgage insurer’s overall results. This effect may occur because the older books will be experiencing declines in revenue and increases in losses with a lower amount of underwriting profit on the new book available to offset these results.

Whether such a lower contribution would in fact occur depends in part on the extent of the volume decline. Even with a substantial decline in volume, there may be offsetting factors that could increase the contribution in the current year. These offsetting factors include higher persistency and a mix of business with higher average premiums, which could have the effect of increasing revenues, and improvements in the economy, which could have the effect of reducing losses. In addition, the effect on the insurer’s overall results from such a lower contribution may be offset by decreases in the mortgage insurer’s expenses that are unrelated to claim or default activity, including those related to lower volume.

The Company’s new insurance written during 2001 — 2003 was $86.1 billion, $92.5 billion and $96.8 billion, respectively and was $49.5 billion and $29.1 billion in the first half of 2003 and 2004, respectively. Consistent with a mid-June 2004 mortgage finance forecast of the Mortgage Bankers Association, which projects that quarterly mortgage originations in the United States are expected to decline materially in 2004 compared to 2003, the Company expects new insurance written for the last two quarters of 2004 will be materially lower than for the comparable period in 2003.

The amount of insurance the Company writes could be adversely affected if lenders and investors select alternatives to private mortgage insurance.

These alternatives to private mortgage insurance include:

While no data is publicly available, the Company believes that 80-10-10 loans and related products are a significant percentage of mortgage originations and that their use, which the Company believes is primarily by borrowers with higher credit scores, continues to increase.

Changes in the business practices of Fannie Mae and Freddie Mac could reduce the Company’s revenues or increase its losses.

The business practices of Fannie Mae and Freddie Mac affect the entire relationship between them and mortgage insurers and include:

The mortgage insurance industry is subject to litigation risk.

Consumers are bringing a growing number of lawsuits against home mortgage lenders and settlement service providers. In recent years, seven mortgage insurers, including the Company’s MGIC subsidiary, have been involved in litigation alleging violations of the Real Estate Settlement Procedures Act, which is commonly known as RESPA. MGIC’s settlement of litigation against it under RESPA became final in October 2003. There can be no assurance that MGIC will not be subject to future litigation under RESPA.

In March 2003 an action against MGIC was filed in Federal District Court in Orlando, Florida seeking certification of a nationwide class of consumers who were required to pay for private mortgage insurance written by MGIC and whose loans were insured at less than MGIC’s “best available rate” based on credit scores obtained by MGIC. (A portion of MGIC’s A minus and subprime premium rates are based in part on the credit score of the borrower.) The action alleges that the Federal Fair Credit Reporting Act (“FCRA”) requires a notice to borrowers of such “adverse action” and that MGIC has violated FCRA by failing to give such notice. The action seeks statutory damages (which in the case of willful violations, in addition to punitive damages, may be awarded in an amount of $100 to $1,000 per class member) and/or actual damages of the persons in the class, and attorneys fees, as well as declaratory and injunctive relief. The action also alleges that the failure to give notice to borrowers in Florida in the circumstances alleged is a violation of Florida’s Unfair and Deceptive Acts and Practices Act and seeks declaratory and injunctive relief for such violation. In December 2003, the Court denied MGIC’s motion seeking dismissal of the portion of the case covering damages under FCRA but dismissed the remainder of the case. In late June 2004, the Court denied the plaintiffs motion to certify the class. There can be no assurance that the outcome of the litigation will not materially affect the Company’s financial position or results of operations. Similar actions have been filed against six other mortgage insurers.

Net premiums written could be adversely affected if the Department of Housing and Urban Development reproposes and adopts a regulation under the Real Estate Settlement Procedures Act that is equivalent to a proposed regulation that was recently withdrawn.

The regulations of the Department of Housing and Urban Development under the Real Estate Settlement Procedures Act prohibit paying lenders for the referral of settlement services, including mortgage insurance, and prohibit lenders from receiving such payments. In July 2002, the Department of Housing and Urban Development proposed a regulation that would exclude from these anti-referral fee provisions settlement services included in a package of settlement services offered to a borrower at a guaranteed price. HUD withdrew this proposed regulation in March 2004. Under the proposed regulation, if mortgage insurance was

required on a loan, the package must include any mortgage insurance premium paid at settlement. Although certain state insurance regulations prohibit an insurer’s payment of referral fees, had this regulation been adopted in this form, the Company’s revenues could have been adversely affected to the extent that lenders offered such packages and received value from the Company in excess of what they could have received were the anti-referral fee provisions of the Real Estate Settlement Procedures Act to apply and if such state regulations were not applied to prohibit such payments.

MGIC INVESTMENT CORPORATION AND SUBSIDIARIES
CONSOLIDATED STATEMENT OF OPERATIONS

NOTE: See “Certain Non-GAAP Financial Measures” for diluted earnings per share contribution from realized gains and C-BASS.

MGIC INVESTMENT CORPORATION AND SUBSIDIARIES
CONSOLIDATED BALANCE SHEET AS OF

CERTAIN NON-GAAP FINANCIAL MEASURES

Management believes the diluted earnings per share contribution from realized gains provides useful information to investors because it shows the after-tax effect that sales of securities from the Company’s investment portfolio, which are discretionary transactions, had on earnings. Management believes the diluted earnings per share contribution from C-BASS provides useful information to investors because it shows the after-tax contribution from this joint venture, which is not controlled by the Company, to earnings.

OTHER INFORMATION

OTHER INFORMATION

ADDITIONAL INFORMATION

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