Exhibit 99.1

CITIZENS BANKING CORPORATION
ANNOUNCES FIRST QUARTER 2005 RESULTS

FLINT, MICHIGAN -— Citizens Banking Corporation announced net income of $20.1 million for the three months ended March 31, 2005. This represents an increase of $2.7 million or 15.1% over the net income of $17.4 million in the first quarter of 2004 and a decrease of $0.2 million or 1.0% over the net income of $20.3 million for the fourth quarter of 2004. Diluted net income per share was $0.46, compared with $0.40 for the same quarter of last year and $0.46 for the fourth quarter of 2004. Annualized returns on average assets and average equity during the first quarter of 2005 were 1.05% and 12.54%, respectively, compared with 0.92% and 10.89% for the first quarter of 2004 and 1.05% and 12.43% for the fourth quarter of 2004.

“We are pleased with the earnings improvement that our continuing commitment to credit quality has enabled us to make over the first quarter of 2004,” stated William R. Hartman, chairman, president and CEO. “The combination of our disciplined, consultative sales process throughout our Corporation, the progress in reducing loans that don’t meet our risk profile, and the success of our Southeast Michigan initiative enabled us to show our second consecutive quarter of growth in the commercial loan portfolio on a basis consistent with our new standards of credit quality,” continued Hartman.

Key Highlights in the Quarter:

•	Commercial and commercial real estate loans grew by $50.8 million from December 31, 2004, primarily as a result of an increased focus on our sales management process. $18.0 million of the growth was attributable to our Oakland County initiative in Southeast Michigan and $32.8 million was largely a result of several new relationships in key Michigan and Wisconsin markets.
•	Net charge-offs declined to $4.2 million or 0.32% of average portfolio loans in the first quarter of 2005 compared with $4.6 million or 0.34% of average portfolio loans in the fourth quarter of 2004 and $6.8 million or 0.53% of average portfolio loans in the first quarter of 2004. The first quarter of 2005 provision for loan losses of $3.0 million was $1.6 million or 34.9% less than the fourth quarter of 2004 and $4.0 million or 57.1% less than the first quarter of 2004.
•	Nonperforming assets continued to decline to their lowest level in more than three years, decreasing $7.1 million or 13.9% to $43.8 million at March 31, 2005 compared with December 31, 2004 and decreasing $18.6 million or 29.9% compared with March 31, 2004.

Balance Sheet

Citizens’ total assets at March 31, 2005 were $7.8 billion, an increase of $84.3 million or 1.1% compared with March 31, 2004 and an increase of $70.7 million or 0.9% from December 31, 2004. These increases were due to growth in total portfolio loans which were partially offset by declines in the investment portfolio. Portfolio loans increased $225.9 million or 4.3% compared with March 31, 2004 and $36.5 million or 0.7% compared with December 31, 2004 as both consumer and commercial loans increased from the end of the first quarter of 2004 despite the $78.5 million reduction at the date of the Illinois Bank sale.

Consumer loans, excluding mortgage loans, increased $165.6 million or 9.1% at March 31, 2005 compared with March 31, 2004 due to a well executed sales process and a number of successful sales campaigns. Total consumer loans, excluding mortgage loans, remained essentially unchanged from December 31, 2004 due to increased competition in home equity rates within our markets and seasonality in the indirect portfolio. Since March 31, 2004, direct consumer loans increased $89.0 million or 8.2% and indirect loans increased $76.6 million or 10.3% due to growth in the recreational vehicle and marine segments from continued emphasis on service and maintaining strong relationships with existing dealers.

Portfolio mortgage loans were $496.0 million at March 31, 2005, an increase of $16.4 million or 3.4% compared with March 31, 2004 and a decrease of $12.3 million or 2.4% from December 31, 2004. The increase in the mortgage portfolio from the end of the first quarter of 2004 occurred due to slower refinance activity. Citizens continues to sell most new fixed rate production into the secondary market and to hold most new ARM volume. Closed mortgage loan volume declined to $108.5 million in the first quarter of 2005 compared with $132.9 million in the fourth quarter of 2004. The decrease in the mortgage portfolio from the end of the fourth quarter of 2004 was due to seasonally reduced activity in construction financing.

Commercial and commercial real estate loans increased $43.9 million or 1.5% at March 31, 2005 compared with March 31, 2004 and increased $50.8 million or 1.8% from December 31, 2004. The increases were a result of continued strong growth in the Southeast Michigan market, increased focus on the sales management process and several new relationships in key Michigan and Wisconsin markets, which were partially offset by a continued reduction of exposure on credits not meeting Citizens’ risk parameters.

Total deposits were $5.3 billion at March 31, 2005, a decrease of $171.4 million or 3.1% compared with March 31, 2004 and essentially unchanged from December 31, 2004. After considering the $155.3 million reduction in deposits as a result of the Illinois Bank sale, the decline in deposits since the first quarter of 2004 occurred largely within time deposits, reflecting Citizens’ less aggressive pricing posture during the low interest rate environment. Additionally, Citizens experienced a shift of customer deposits from interest-bearing demand and time deposits to promotional rate savings products throughout the year. Core deposits, which exclude time deposits, totaled $3.6 billion at March 31, 2005, essentially unchanged from March 31, 2004 and representing a decrease of $110.8 million or 3.0% from December 31, 2004. The decrease in core deposits from the end of the fourth quarter of 2004 is largely the result of a decline in interest-bearing checking and promotional savings products as the higher rate environment is prompting clients to migrate their funds into time deposits with higher yields and to promotional rate products within the market. Time deposits totaled $1.7 billion at March 31, 2005, a decrease of $190.1 million or 10.0% compared with March 31, 2004 and an increase of $100.6 million or 6.2% from December 31, 2004.

Credit Quality

Nonperforming assets totaled $43.8 million at March 31, 2005, a decrease of $18.6 million or 29.9% compared with March 31, 2004 and a decrease of $7.1 million or 13.9% compared with December 31, 2004. Nonperforming assets at March 31, 2005 represented 0.80% of total loans plus other repossessed assets acquired compared with 1.20% at March 31, 2004 and 0.94% at December 31, 2004. Loans added to the commercial nonperforming loan category decreased to $11.2 million in the first quarter of 2005 compared with $11.7 million in the first quarter of 2004 and $18.4 million in the fourth quarter of 2004 while loans removed from that category totaled $15.4 million for the first quarter of 2005 compared with $25.1 million in the first quarter of 2004 and $18.9 million in the fourth quarter of 2004.

Net charge-offs decreased to $4.2 million or 0.32% of average portfolio loans in the first quarter of 2005 compared with $6.8 million or 0.53% of average portfolio loans in the first quarter of 2004 and $4.6 million or 0.34% of average portfolio loans in the fourth quarter of 2004. The 8.0% decrease in net charge-offs from the fourth quarter of 2004 was due to an overall reduction in the level of commercial loan portfolio charge-offs reflecting a continued improvement in the overall risk of the portfolio. The allowance for loan losses totaled $120.9 million or 2.23% of portfolio loans at March 31, 2005, a decrease of $2.8 million and $1.2 million from March 31, 2004 and December 31, 2004, respectively.

The provision for loan losses decreased to $3.0 million in the first quarter of 2005 compared with $7.0 million in the first quarter of 2004 and $4.6 million in the fourth quarter of 2004. The reduction in the provision for loan losses reflects a decrease in the level of net charge-offs as well as a reduction in the level of specific reserves.

Based on current business trends and continued improvement in nonperforming loans and the overall risk in the loan portfolio, Citizens anticipates net charge-offs and provision expense in the second quarter will be consistent with the first quarter of 2005.

Net Interest Margin and Net Interest Income

Net interest margin decreased to 3.96% in the first quarter of 2005 compared with 4.01% in the first quarter of 2004 and 3.97% in the fourth quarter of 2004. The decrease in net interest margin compared with the first quarter of 2004 resulted from an increase in the cost of funds that outpaced the increase in the earning asset yield. The earning asset yield was slowed by residential mortgage loan yield and commercial loan pricing spread declines as Citizens continued to underwrite higher quality commercial loans with normal spreads replacing lower quality commercial loans with higher spreads. The decrease in net interest margin compared with the fourth quarter of 2004 was due to growth in higher yielding deposit products and pricing compression in commercial loans.

Net interest income was $68.2 million in the first quarter of 2005 compared with $68.3 million in the first quarter of 2004 and $68.5 million in the fourth quarter of 2004. The decrease in net interest income compared with the first quarter of 2004 was driven by a lower net interest margin, which was partially offset by growth in average earning assets. The decrease compared with the previous quarter resulted from a lower net interest margin, which was partially offset by an increase in average earning assets of $75.4 million caused by the growth in the commercial and commercial real estate loan portfolios.

In the second quarter of 2005 Citizens anticipates net interest income will be consistent with or slightly higher than the first quarter of 2005 as a result of more days in the quarter and continued loan growth, partially offset by anticipated margin compression.

Noninterest Income

Noninterest income for the first quarter of 2005 remained essentially unchanged from the first quarter of 2004 at $22.5 million. Increases in deposit service charges, trust fees, and mortgage fees were offset by decreases in brokerage and investment fees and other income. Compared with the fourth quarter of 2004, noninterest income decreased $1.2 million or 5.0% as a result of declines in deposit service charges, trust fees, mortgage and other loan income, and brokerage and investment fees.

Deposit service charges for the first quarter of 2005 increased $0.2 million or 3.1% to $8.3 million compared with the first quarter of 2004. The increase was the result of initiatives implemented over the last seven quarters which improved fee waiver management and slight increases in certain fees. Deposit service charges decreased $0.5 million or 6.0% in the first quarter of 2005 compared with the fourth quarter of 2004. This decrease was due to the rising rate environment, which resulted in higher customer earnings credits against commercial deposit service charges based on commercial deposit balances, and lower overdraft fees as a result of fewer processing days in the first quarter of 2005.

Trust fees increased $0.1 million or 2.4% to $4.4 million in the first quarter of 2005 compared with the first quarter of 2004 due to Citizens’ sales management processes implemented during the first quarter of 2004 that focused on relationship management and new business development strategies. Trust fees decreased by $0.4 million or 8.0% from the fourth quarter of 2004 due to seasonal differences in the timing of fees. Total trust assets under administration decreased $268.3 million to $2.6 billion at March 31, 2005 compared with March 31, 2004 and decreased $75.1 million compared with December 31, 2004. The decline in trust assets from March 31, 2004 was due to the reduction of a large institutional relationship in the second and fourth quarters of 2004 and the exit of custody assets related to three relationships in the second quarter of 2004 and the first quarter of 2005. The decline in trust assets from December 31, 2004 was due to weaker financial markets and two of the aforementioned custody relationship exits.

Mortgage and other loan income increased $0.1 million or 4.6% to $2.4 million in the first quarter of 2005 compared with the first quarter of 2004, reflecting an improvement in the execution of the secondary market sales. Mortgage and other loan income decreased by $0.2 million or 7.9% compared with the fourth quarter of 2004 due to a decline in commercial letter of credit fees. The decline was the result of a change in Citizens’ accounting policy, which now defers these fees over the life of the underlying loans.

Brokerage and investment fees decreased $0.2 million or 10.3% to $1.6 million in the first quarter of 2005 compared with the first quarter of 2004 and decreased by $0.1 million or 7.8% compared with the fourth quarter of 2004. These declines were due to lower annuity sales.

Other noninterest income decreased $0.4 million or 7.2% to $5.0 million for the first quarter of 2005 compared with the first quarter of 2004 due to gains recognized upon the sale of former branch and other bank premises in the first quarter of 2004. Other noninterest income increased $0.1 million or 2.3% compared with the fourth quarter of 2004 due to a performance-related penalty received from a third party vendor, a preference payment on Citizens’ membership interest in the PULSE ATM network and a bank-owned life insurance policy payout in the first quarter of 2005 which were partially offset by reduced gains on the sale of bank-owned equipment.

Citizens anticipates total noninterest income in the second quarter will be consistent with or slightly lower than the first quarter of 2005 due to lower mortgage activity and anticipated seasonal improvement in service charges.

Noninterest Expense

Noninterest expense was essentially unchanged at $60.6 million in the first quarter of 2005 compared with $60.5 million in the first quarter of 2004 and was down $0.5 million or 0.8% from the fourth quarter of 2004. The variance from the fourth quarter of 2004 is a result of decreases in equipment, advertising, other loan fees, and other expenses, which were partially offset by increases in salaries and employee benefits, occupancy, and professional services.

Salaries and employee benefits increased $1.4 million or 4.4% to $33.4 million in the first quarter of 2005 compared with the first quarter of 2004 and increased $2.0 million or 6.5% compared with the fourth quarter of 2004. Despite recognizing $0.9 million in severance, salary costs continued to decline in the first quarter of 2005 as a result of reduced headcount. However, incentive expense increased during the current quarter due to the realignment of incentive compensation programs. Employee benefits increased due to higher retirement benefit costs and payroll taxes. Citizens had 2,175 full time equivalent employees at March 31, 2005, down from 2,302 at March 31, 2004 and 2,215 at December 31, 2004.

Occupancy costs increased $0.2 million or 4.1% to $5.6 million in the first quarter of 2005 compared with the first quarter of 2004 and increased $0.5 million or 9.5% compared with the fourth quarter of 2004. These increases were largely due to building rent and other expenses related to the opening of new branches and regional hubs in Southeast Michigan throughout 2004.

Professional services expense increased $0.3 million or 6.9% to $4.2 million in the first quarter of 2005 compared with the first quarter of 2004 and increased $0.3 million or 7.4% compared with the fourth quarter of 2004. The increases were a result of expenses related to work performed in 2005 to complete the evaluation, documentation, and testing of internal controls and issuance of the related reports to comply with Sarbanes-Oxley Section 404.

Equipment related costs decreased $0.3 million or 9.4% to $3.3 million for the first quarter of 2005 compared with the first quarter of 2004 and decreased $0.3 million or 7.6% compared with the fourth quarter of 2004. These decreases were the result of lower equipment depreciation expense associated with the first quarter of 2004 change in Citizens’ capitalization policy, along with reductions in software maintenance costs and spending on non-capital equipment.

Data processing services decreased $0.3 million or 7.6% to $3.4 million for the first quarter of 2005 compared with the first quarter of 2004 due to contract savings negotiated in the third quarter of 2004 with Citizens’ core processing provider. Data processing services increased $0.3 million or 9.6% compared with the fourth quarter of 2004 due to a price increase and additional processing costs related to year-end reporting.

Advertising and public relations expense decreased $0.4 million or 18.6% to $1.7 million in the first quarter of 2005 compared with the first quarter of 2004, and decreased $1.2 million or 39.9% compared with the fourth quarter of 2004. These decreases were largely due to advertising and marketing expenses incurred during the first quarter of 2004 to support Citizens’ Southeast Michigan initiative and the Michigan re-branding project during the fourth quarter of 2004.

Other loan fee expense decreased $0.8 million or 66.8% to $0.4 million for the first quarter of 2005 compared with the first quarter of 2004 and decreased $0.5 million or 55.3% compared with the fourth quarter of 2004. These decreases were largely the result of lower provisioning to fund the reserve for

unused commitments due to improved credit quality and higher line utilization in the first quarter of 2005 as well as lower loan processing costs.

Other noninterest expenses were essentially unchanged at $8.7 million for the first quarter of 2005 compared with $8.8 million in the first quarter of 2004 and decreased $1.7 million or 16.5% compared with the fourth quarter of 2004. The decrease was the result of losses from litigation settlements that were recognized in the fourth quarter of 2004, seasonally reduced spending for training and travel, and supplies.

Citizens anticipates that noninterest expenses for the second quarter will be lower than the first quarter of 2005 due to anticipated reductions in benefits, incentives, and other expenses.

Other News

Michigan-Wisconsin Branding Update

As previously announced, Citizens is planning to re-brand its F&M Bank-Wisconsin locations as Citizens Bank on April 25, 2005. The re-branding will include new Citizens Bank signage at all of the company’s Wisconsin locations and the replacement of the F&M Bank trade name and brand image with the Citizens Bank trade name and brand image on all materials and products. This change is intended to bring all of our 171 banking offices in Wisconsin and Michigan under a fresh, new image consistent with the “Let’s Make It Happen” culture we are developing.

START Education Loan Program

Citizens introduced the START Education Loan Program in March 2005. START Education loans are available to finance undergraduate, graduate, continuing education and K-12 studies. Benefits of the START Education Loan Program include competitive interest rates and a quick application and funding process.

Dominion Bond Issues Debt Rating

Dominion Bond Rating Service (DBRS) has initiated coverage on Citizens Banking Corporation and has assigned issuer and senior debt ratings of BBB (high), subordinated debt rating of BBB and short-term instrument rating of R-2 (high). A deposit and senior debt rating of A (low) and a short-term instrument rating of R-1 (low) have been assigned to Citizens Bank and F&M Bank — Iowa. Trends on all ratings are stable.

This rating relates to the company’s debt obligations, and is not a rating of the company’s common stock. Investors should not construe this rating as an indicator of the future performance of the company’s common stock.

Stock Repurchase Program

During the first quarter of 2005, Citizens repurchased a total of 86,000 shares of its stock at an average price of $30.44. As of March 31, 2005, 2,764,200 shares remain to be purchased under the program approved by the company’s Board of Directors on October 16, 2003.

Dividend Announcement

The Board of Directors of Citizens Banking Corporation declared a cash dividend of $0.285 per share of common stock. The dividend is payable on May 12, 2005, to shareholders of record on May 2, 2005.

Annual Meeting

Citizens Banking Corporation’s annual meeting of shareholders will be held on Tuesday, May 17, 2005, at 10:00 a.m. EDT at the Holiday Inn Gateway Centre, Flint, Michigan.

Investor Conference Call

William R. Hartman, chairman, president and CEO, Charles D. Christy, CFO, John D. Schwab, chief credit officer, and Martin E. Grunst, treasurer will review the quarter’s results in a conference call for investors and analysts beginning at 10:00am EDT on Friday, April 22, 2005.

A live audio web cast is available at http://www.vcall.com/CEPage.asp?ID=91356 To participate in the conference call, please call the number below approximately 10 minutes prior to the scheduled conference time: US/Canada Dial-In Number: (877) 407-8031 International Dial-In Number: (201) 689-8031 Conference ID: 00146639 Conference Name: “Citizens Banking Corporation First Quarter Earnings Conference Call” R.S.V.P. is not required.

A playback of the conference call will be available after 12:00pm EDT through May 6, 2005, by dialing US/Canada Dial-In Number: (877) 660-6853 or International Dial-In Number: (201) 612-7415, Account Number 286, Conference ID: 146639. Also, a playback of the call can be accessed via Citizens’ web site, through the Investor Relations section at www.citizensonline.com

Corporate Profile

Citizens Banking Corporation is a diversified financial services company providing a full range of commercial, consumer, mortgage banking, trust and financial planning services to a broad client base. Citizens operates 182 branch, private banking, and financial center locations and 187 ATMs throughout Michigan, Wisconsin, and Iowa.

Safe Harbor Statement

Discussions in this release that are not statements of historical fact (including statements that include terms such as “will” “may,” “should,” “believe,” “expect,” “anticipate,” “estimate,” “intend,” and “plan”) are forward-looking statements that involve risks and uncertainties, and Citizens’ actual future results could materially differ from those discussed. Factors that could cause or contribute to such differences include, without limitation, adverse changes in Citizens’ loan and lease portfolios and the resulting credit risk-related losses and expenses (including losses due to fraud and economic factors), Citizens’ future lending and collections experience and the potential inadequacy of Citizens’ loan loss reserves, interest rate fluctuations and the effects on net interest income of changes in Citizens’ interest rate risk position, the potential inability to hedge certain risks economically, other adverse changes in economic or financial market conditions, the effects of terrorist attacks and potential attacks, Citizens’ potential inability to continue to attract core deposits, Citizens’ potential inability to continue to obtain third party financing on favorable terms, adverse changes in competition and pricing environments, Citizens’ potential failure to maintain or improve loan quality levels and origination volume, unanticipated expenses and payments relating to litigation brought against Citizens from time to time, unanticipated technological changes that require major capital expenditures, adverse changes in applicable laws and regulatory requirements, the potential lack of market acceptance of Citizens’ products and services, adverse changes in Citizens’ relationship with major customers, changes in accounting rules that negatively impact results of operations or capital, the potential inadequacy of Citizens’ business continuity plans, the potential failure of Citizens’ external vendors to fulfill their contractual obligations to Citizens, Citizens’ potential inability to integrate acquired operations or complete its restructuring, unanticipated environmental liabilities or costs, impairment of the ability of the banking subsidiaries to pay dividends to the holding company parent, Citizens’ success in managing the risks involved in the foregoing, and other risks and uncertainties detailed from time to time in its filings with the Securities and Exchange Commission. Other factors not currently anticipated by management may also materially and adversely affect Citizens’ results of operations. There can be no assurance that the future results will meet expectations. While Citizens believes that its forward-looking statements are reasonable, you should not place undue reliance on any forward-looking statement. In addition, these statements speak only as of the date made. Citizens does not undertake, and expressly disclaims any obligation, to update or alter its statements whether as a result of new information, future events or otherwise, except as required by applicable law.

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(Financial highlights follow)

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Average Balances, Yields and Rates

Summary of Loan Loss Experience
Citizens Banking Corporation and Subsidiaries