EXHIBIT 99.1

Greg Parker

Investor Relations

210/220-5632

        or

Renee Sabel

Media Relations

210/220-5416

FOR IMMEDIATE RELEASE

JANUARY 27, 2010

CULLEN/FROST REPORTS STEADY 4^th QUARTER RESULTS,

ANNUAL EARNINGS FOR 2009

Consistent Performance in Challenging Economy

• Record deposit levels

• Non-performing loans decline

• Capital ratios remain strong

SAN ANTONIO – Cullen/Frost Bankers, Inc. today reported results for the fourth quarter and full year of 2009, as the Texas financial services leader continued to operate well in a challenging economy and extended low rate environment.

Cullen/Frost reported net income for the fourth quarter of 2009 of $51.5 million, or $.86 per diluted common share, compared to fourth quarter 2008 earnings of $53.0 million, or $.89 per diluted common share. For the fourth quarter of 2009, returns on average assets and equity were 1.25 percent and 10.70 percent respectively, compared to 1.47 percent and 12.79 percent for the same period of 2008.

The company also reported annual earnings for 2009 of $179.0 million, or $3.00 per diluted common share, compared to 2008 earnings of $207.3 million, or $3.50 per diluted common share. For the year, returns on average assets and equity were 1.14 percent and 9.78 percent respectively, compared to the 1.51 percent and 13.11 percent reported in 2008.

During the fourth quarter of 2009, Cullen/Frost saw non-performing assets decline by $40.6 million from the previous quarter. In addition, the company recognized a pre-tax net gain of $16.3 million related to the prepayment of certain debt and the termination of the related interest rate swap.

“Overall, our company performed well in 2009 in the midst of a very difficult economy,” said Dick Evans, Cullen/Frost chairman and CEO. “I was pleased to see a nearly $2 billion increase in average deposits for the year, a record for Cullen/Frost, from customers who see Frost as a safe haven. Today we have strong capital levels — stronger even than when we declined TARP 15 months ago — and are well positioned for growth.

“I was encouraged to see a $40 million reduction in non-performers this quarter, and credit quality continues to be at manageable levels. Although the provision was higher, it exceeded net charge-offs, increasing the reserve level to 1.50 percent of loans,” said Evans.

Evans said that customer uncertainty about the Texas economy continued to impact the lending environment, noting that loans are down despite a strong calling effort that has brought in new relationships. Business owners, Evans said, are largely on the sidelines, paying down debt and reducing inventory.

“We are working harder in this environment to grow the number of relationships and to broaden and deepen existing ones. When the economy begins to grow again, we will be well positioned to reap the benefits of this effort.

“In November of 2009 we completed construction on the $50 million Frost Technology Center, a state-of-the-art facility that ensures our capacity to meet future data and information technology needs as the company grows. We have also updated our technology infrastructure and enhanced the security of our data processing systems and customer information.”

Evans said the company opened four new financial centers in 2009, including locations in Austin, San Antonio and Plano in the Dallas region. Late in the year, Frost opened a financial center in Houston that was a relocation of an older facility. The company also introduced Frost Mobile in 2009, which has been well received by customers who appreciate the added flexibility and convenience of doing business with Frost from their mobile phones.

“We have a seasoned staff who knows how to adapt in a tough environment. We are fortunate to have that experience level and to operate in a pro-business state. I continue to be optimistic about our prospects.

“I appreciate the efforts of our outstanding employees around the state, and I am inspired by their energy, their expertise and their commitment to our culture and to taking great care of our customers.”

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For the year ended December 31, 2009, average annual total loans were $8.7 billion, an increase of 4.1 percent compared to $8.3 billion for the previous year. Average annual total deposits for 2009 rose to $12.4 billion, up 17.9 percent over the $10.5 billion reported in 2008. Net interest income on a taxable-equivalent basis grew to $577.7 million, a 4.2 percent increase over the $554.4 million reported a year earlier, reflecting the impact of increasing volumes. For 2009, non-interest income rose to $293.7 million, up 2.2 percent over the $287.3 million reported for 2008, while non-interest expense increased 9.4 percent over the previous year to $532.2 million and was heavily impacted by $21.2 million in higher FDIC insurance premiums.

Noted financial data for the fourth quarter:

• Tier 1 and Total Risk-Based Capital Ratios for the Corporation at the end of the fourth quarter of 2009 were 11.91 percent and 14.19 percent, respectively and are in excess of well capitalized levels. The ratio of tangible common equity to tangible assets was 8.56 percent at the end of the fourth quarter of 2009, compared to 8.37 percent for the same quarter last year.

• Net interest income on a taxable-equivalent basis for the fourth quarter totaled $150.7 million, a 4.9 percent increase from the $143.7 million reported for the fourth quarter of 2008. This increase primarily resulted from an increase in the average volume of earning assets and was partly offset by a decrease in the net interest margin. The net interest margin was 4.20 percent for the fourth quarter, compared to 4.60 percent for the fourth quarter of 2008 and 4.12 percent for the third quarter of 2009.

• Non-interest income for the fourth quarter of 2009 was $86.3 million, up 24.8 percent over the $69.2million reported a year earlier.

Other income increased $16.2 million from the fourth quarter of 2008 due primarily to the $17.7 million gain recognized from the termination of the interest rate swap associated with certain debt that was paid off early.

Trust income was $17.7 million, compared to $17.5 million for the fourth quarter of 2008, with most of this increase resulting from higher investment fees due to increases in the equities market. Investment fees are assessed based on the market value of trust assets, which totaled $22.7 billion at December 31, 2009 up $1 billion from the fourth quarter a year ago. This increase was partially offset by lower oil and gas fees from the same period last year, as oil and natural gas prices have decreased, impacting the amount of royalties received.

Service charges on deposits were $26.0 million, an increase of $2.3 million or 9.8 percent, compared to $23.7 million reported for the previous year’s fourth quarter. Impacting this was a $2.0

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million increase in service charges on commercial accounts, resulting from higher treasury management fees. A drop in the earnings credit rate for commercial accounts compared to a year earlier, impacted treasury management fees. When interest rates are lower, customers earn less credit for their deposit balances, which, in turn, increases the amount of service charges to be paid for through fees.

• Non-interest expense for the fourth quarter of 2009 was $134.2 million, up $10.7 million or 8.6 percent from the $123.5 million for the fourth quarter of 2008. A large part of this increase is due to higher FDIC insurance expense of $3.3 million. Total salaries were up $268 thousand over the same quarter a year earlier, as a result of normal annual merit and market increases, offset by a decrease in incentive compensation. Employees benefits were up $2.2 million or 21.3 percent, primarily due to increases in expenses related to the company’s medical costs, 401(k) and profit sharing plans, and retirement plan. Net occupancy expense was $11.5 million, an increase of $1.1 million from the fourth quarter last year, due primarily to expenses associated with new locations. Expenses for furniture and equipment were up $2.1 million to $12.1 million, due mainly to increases in depreciation expense related to furniture and fixtures, primarily for new locations, amortized software and software maintenance expense. Other expense was $32.5 million, a $2.1 million increase when compared to the fourth quarter of 2008. Included in other expense is a $1.4 million prepayment penalty on the early termination of certain debt.

• For the fourth quarter of 2009, the provision for possible loan losses was $22.3 million, compared to net charge-offs of $20.1 million. For the fourth quarter of 2008, the provision for possible loan losses was $8.6 million, compared to net charge offs of $5.4 million. The allowance for possible loan losses as a percentage of total loans was 1.50 percent at December 31, 2009, compared to 1.25 percent at year-end 2008. Non-performing assets were $180.2 million at year-end, compared to $220.9 million the previous quarter, and $78.0 million at year-end 2008.

Cullen/Frost Bankers, Inc. will host a conference call on Wednesday, January 27, 2010 at 10:00 a.m. Central Time (CT) to discuss the results for the quarter and the year. The media and other interested parties are invited to access the call in a “listen only” mode at 800-944-6430. Digital playback of the conference call will be available after 12:00 p.m. CT until midnight Sunday, January 31, 2010 at 800-642-1687, with the Conference ID# of 49680053. The call will also be available by webcast at the URL listed below and available for playback after 2:00 p.m. CT. After entering the website, www.frostbank.com, go to “About Frost” on the top navigation bar, then click on Investor Relations.

Cullen/Frost Bankers, Inc. (NYSE: CFR) is a financial holding company, headquartered in San Antonio, with assets of $16.3 billion at December 31, 2009. The corporation provides a full range of commercial and

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consumer banking products, investment and brokerage services, insurance products and investment banking services. Its subsidiary, Frost Bank, operates more than 100 financial centers across Texas in the Austin, Corpus Christi, Dallas, Fort Worth, Houston, Rio Grande Valley and San Antonio regions. Founded in 1868, Frost is the largest banking organization headquartered in Texas that operates only in Texas, with a legacy of helping clients with their financial needs during three centuries.

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Forward-Looking Statements and Factors that Could Affect Future Results

Certain statements contained in this Earnings Release that are not statements of historical fact constitute forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 (the “Act”), notwithstanding that such statements are not specifically identified as such. In addition, certain statements may be contained in the Corporation’s future filings with the SEC, in press releases, and in oral and written statements made by or with the approval of the Corporation that are not statements of historical fact and constitute forward-looking statements within the meaning of the Act. Examples of forward-looking statements include, but are not limited to: (i) projections of revenues, expenses, income or loss, earnings or loss per share, the payment or nonpayment of dividends, capital structure and other financial items; (ii) statements of plans, objectives and expectations of Cullen/Frost or its management or Board of Directors, including those relating to products or services; (iii) statements of future economic performance; and (iv) statements of assumptions underlying such statements. Words such as “believes”, “anticipates”, “expects”, “intends”, “targeted”, “continue”, “remain”, “will”, “should”, “may” and other similar expressions are intended to identify forward-looking statements but are not the exclusive means of identifying such statements.

Forward-looking statements involve risks and uncertainties that may cause actual results to differ materially from those in such statements. Factors that could cause actual results to differ from those discussed in the forward-looking statements include, but are not limited to:

• Local, regional, national and international economic conditions and the impact they may have on the Corporation and its customers and the Corporation’s assessment of that impact.

• Volatility and disruption in national and international financial markets.

• Government intervention in the U.S. financial system.

• Changes in the level of non-performing assets and charge-offs.

• Changes in estimates of future reserve requirements based upon the periodic review thereof under relevant regulatory and accounting requirements.

• The effects of and changes in trade and monetary and fiscal policies and laws, including the interest rate policies of the Federal Reserve Board.

• Inflation, interest rate, securities market and monetary fluctuations.

• Political instability.

• Acts of God or of war or terrorism.

• The timely development and acceptance of new products and services and perceived overall value of these products and services by users.

• Changes in consumer spending, borrowings and savings habits.

• Changes in the financial performance and/or condition of the Corporation’s borrowers.

• Technological changes.

• Acquisitions and integration of acquired businesses.

• The ability to increase market share and control expenses.

• Changes in the competitive environment among financial holding companies and other financial service providers.

• The effect of changes in laws and regulations (including laws and regulations concerning taxes, banking, securities and insurance) with which the Corporation and its subsidiaries must comply.

• The effect of changes in accounting policies and practices, as may be adopted by the regulatory agencies, as well as the Public Company Accounting Oversight Board, the Financial Accounting Standards Board and other accounting standard setters.

• Changes in the Corporation’s organization, compensation and benefit plans.

• The costs and effects of legal and regulatory developments including the resolution of legal proceedings or regulatory or other governmental inquiries and the results of regulatory examinations or reviews.

• Greater than expected costs or difficulties related to the integration of new products and lines of business.

• The Corporation’s success at managing the risks involved in the foregoing items.

Forward-looking statements speak only as of the date on which such statements are made. The Corporation undertakes no obligation to update any forward-looking statement to reflect events or circumstances after the date on which such statement is made, or to reflect the occurrence of unanticipated events.

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Cullen/Frost Bankers, Inc.

CONSOLIDATED FINANCIAL SUMMARY (UNAUDITED)

(In thousands, except per share amounts)

	2009												2008
	4th Qtr			3rd Qtr			2nd Qtr			1st Qtr			4th Qtr
CONDENSED INCOME STATEMENTS
Net interest income	$	138,594		$	133,989		$	134,464		$	129,632		$	138,081
Net interest income(1)		150,743			144,915			144,325			137,733			143,707
Provision for possible loan losses		22,250			16,940			16,601			9,601			8,550
Non-interest income:
Trust fees		17,669			16,755			16,875			15,969			17,483
Service charges on deposit accounts		26,017			26,395			25,152			24,910			23,697
Insurance commissions and fees		6,734			8,505			7,106			10,751			6,470
Other charges, commissions and fees		7,804			6,845			6,288			6,762			8,407
Net gain (loss) on securities transactions		(1,309	)		—			49			—			(133	)
Other		29,430			10,991			12,536			11,472			13,274
Total non-interest income		86,345			69,491			68,006			69,864			69,198
Non-interest expense:
Salaries and wages		58,736			58,591			56,540			56,776			58,468
Employee benefits		12,756			13,445			13,783			15,240			10,517
Net occupancy		11,523			11,111			10,864			10,690			10,384
Furniture and equipment		12,065			11,133			10,662			10,363			10,010
Deposit insurance		5,126			4,643			11,667			4,376			1,785
Intangible amortization		1,473			1,564			1,719			1,781			1,929
Other		32,537			31,747			31,054			30,273			30,450
Total non-interest expense		134,216			132,234			136,289			129,499			123,543
Income before income taxes		68,473			54,306			49,580			60,396			75,186
Income taxes		16,979			9,607			11,721			15,414			22,223
Net income	$	51,494		$	44,699		$	37,859		$	44,982		$	52,963
PER SHARE DATA
Net income - basic	$	0.86		$	0.75		$	0.64		$	0.76		$	0.89
Net income - diluted		0.86			0.75			0.63			0.76			0.89
Cash dividends		0.43			0.43			0.43			0.42			0.42
Book value at end of quarter		31.55			31.80			30.12			30.34			29.68
OUTSTANDING SHARES
Period-end shares		60,038			59,929			59,653			59,423			59,416
Weighted-average shares - basic		59,762			59,537			59,331			59,189			59,171
Dilutive effect of stock compensation		64			91			119			75			311
Weighted-average shares - diluted		59,826			59,628			59,450			59,264			59,482
SELECTED ANNUALIZED RATIOS
Return on average assets		1.25	%		1.11	%		0.98	%		1.23	%		1.47	%
Return on average equity		10.70			9.70			8.35			10.33			12.79
Net interest income to average earning assets(1)		4.20			4.12			4.28			4.33			4.60

⁽¹⁾ Taxable-equivalent basis assuming a 35% tax rate.

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Cullen/Frost Bankers, Inc.

CONSOLIDATED FINANCIAL SUMMARY (UNAUDITED)

	2009												2008
	4th Qtr			3rd Qtr			2nd Qtr			1st Qtr			4th Qtr
BALANCE SHEET SUMMARY
($ in millions)
Average Balance:
Loans	$	8,440		$	8,582		$	8,784		$	8,809		$	8,712
Earning assets		14,501			14,121			13,632			12,942			12,435
Total assets		16,335			16,047			15,519			14,881			14,347
Non-interest-bearing demand deposits		4,574			4,343			4,138			3,971			3,803
Interest-bearing deposits		8,644			8,453			8,045			7,487			7,106
Total deposits		13,218			12,796			12,183			11,458			10,909
Shareholders’ equity		1,909			1,829			1,818			1,766			1,647
Period-End Balance:
Loans	$	8,368		$	8,519		$	8,644		$	8,779		$	8,844
Earning assets		14,437			14,436			13,855			13,530			13,001
Goodwill and intangible assets		547			549			549			551			551
Total assets		16,288			16,158			15,785			15,331			15,034
Total deposits		13,313			12,922			12,497			12,033			11,509
Shareholders’ equity		1,894			1,906			1,797			1,803			1,764
Adjusted shareholders’ equity(1)		1,740			1,709			1,675			1,650			1,626
ASSET QUALITY
($ in thousands)
Allowance for possible loan losses	$	125,309		$	123,122		$	122,501		$	114,168		$	110,244
as a percentage of period-end loans		1.50	%		1.45	%		1.42	%		1.30	%		1.25	%
Net charge-offs	$	20,063		$	16,319		$	8,268		$	5,677		$	5,415
Annualized as a percentage of average loans		0.94	%		0.75	%		0.38	%		0.26	%		0.25	%
Non-performing assets:
Non-accrual loans	$	146,867		$	191,754		$	168,805		$	114,233		$	65,174
Foreclosed assets		33,312			29,112			21,478			13,533			12,866
Total	$	180,179		$	220,866		$	190,283		$	127,766		$	78,040
As a percentage of:
Total loans and foreclosed assets		2.14	%		2.58	%		2.20	%		1.45	%		0.88	%
Total assets		1.11			1.37			1.21			0.83			0.52
CONSOLIDATED CAPITAL RATIOS
Tier 1 Risk-Based Capital Ratio		11.91	%		11.49	%		10.91	%		10.64	%		10.30	%
Total Risk-Based Capital Ratio		14.19			13.72			13.34			12.98			12.58
Leverage Ratio		8.50			8.47			8.50			8.70			8.80
Equity to Assets Ratio (period-end)		11.63			11.80			11.38			11.76			11.73
Equity to Assets Ratio (average)		11.69			11.40			11.72			11.87			11.48

⁽¹⁾ Shareholders’ equity excluding accumulated other comprehensive income (loss).

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Cullen/Frost Bankers, Inc.

CONSOLIDATED FINANCIAL SUMMARY (UNAUDITED)

(In thousands, except per share amounts)

	Year Ended December 31
	2009			2008			2007			2006			2005
CONDENSED INCOME STATEMENTS
Net interest income	$	536,679		$	534,025		$	518,737		$	469,163		$	391,266
Net interest income(1)		577,716			554,353			534,195			479,138			398,938
Provision for possible loan losses		65,392			37,823			14,660			14,150			10,250
Non-interest income:
Trust fees		67,268			74,554			70,359			63,469			58,353
Service charges on deposit accounts		102,474			87,566			80,718			77,116			78,751
Insurance commissions and fees		33,096			32,904			30,847			28,230			27,731
Other charges, commissions and fees		27,699			35,557			32,558			28,105			23,125
Net gain (loss) on securities transactions		(1,260	)		(159	)		15			(1	)		19
Other		64,429			56,900			53,734			43,828			42,400
Total non-interest income		293,706			287,322			268,231			240,747			230,379
Non-interest expense:
Salaries and wages		230,643			225,943			209,982			190,784			166,059
Employee benefits		55,224			47,219			47,095			46,231			41,577
Net occupancy		44,188			40,464			38,824			34,695			31,107
Furniture and equipment		44,223			37,799			32,821			26,293			23,912
Deposit insurance		25,812			4,597			1,220			1,162			1,110
Intangible amortization		6,537			7,906			8,860			5,628			4,859
Other		125,611			122,717			123,644			105,560			98,383
Total non-interest expense		532,238			486,645			462,446			410,353			367,007
Income before income taxes		232,755			296,879			309,862			285,407			244,388
Income taxes		53,721			89,624			97,791			91,816			78,965
Net income	$	179,034		$	207,255		$	212,071		$	193,591		$	165,423
PER SHARE DATA
Net income - basic	$	3.00		$	3.51		$	3.59		$	3.48		$	3.14
Net income - diluted		3.00			3.50			3.57			3.44			3.09
Cash dividends		1.71			1.66			1.54			1.32			1.165
Book value		31.55			29.68			25.18			23.01			18.03
OUTSTANDING SHARES
Period-end shares		60,038			59,416			58,662			59,839			54,483
Weighted-average shares -basic		59,456			58,846			58,952			55,467			52,481
Dilutive effect of stock compensation		58			324			645			1,043			1,235
Weighted-average shares - diluted		59,514			59,170			59,597			56,510			53,716
SELECTED ANNUALIZED RATIOS
Return on average assets		1.14	%		1.51	%		1.63	%		1.67	%		1.63	%
Return on average equity		9.78			13.11			15.20			18.03			18.78
Net interest income to average earning assets(1)		4.23			4.67			4.69			4.67			4.45

⁽¹⁾ Taxable-equivalent basis assuming a 35% tax rate.

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Cullen/Frost Bankers, Inc.

CONSOLIDATED FINANCIAL SUMMARY (UNAUDITED)

	Year Ended December 31
	2009			2008			2007			2006			2005
BALANCE SHEET SUMMARY
($ in millions)
Average Balance:
Loans	$	8,653		$	8,314		$	7,464		$	6,524		$	5,594
Earning assets		13,804			11,868			11,340			10,203			8,969
Total assets		15,702			13,685			13,042			11,581			10,143
Non-interest-bearing demand deposits		4,259			3,615			3,524			3,334			3,009
Interest bearing deposits		8,161			6,916			6,689			5,850			5,124
Total deposits		12,420			10,531			10,213			9,184			8,133
Shareholders’ equity		1,831			1,580			1,395			1,074			881
Period-End Balance:
Loans	$	8,368		$	8,844		$	7,769		$	7,373		$	6,085
Earning assets		14,437			13,001			11,556			11,461			10,197
Goodwill and intangible assets		547			551			558			563			184
Total assets		16,288			15,034			13,485			13,224			11,741
Total deposits		13,313			11,509			10,530			10,388			9,146
Shareholders’ equity		1,894			1,764			1,477			1,377			982
Adjusted shareholders’ equity(1)		1,740			1,626			1,484			1,432			1,033
ASSET QUALITY
($ in thousands)
Allowance for possible loan losses	$	125,309		$	110,244		$	92,339		$	96,085		$	80,325
As a percentage of period-end loans		1.50	%		1.25	%		1.19	%		1.30	%		1.32	%
Net charge-offs:	$	50,327		$	19,918		$	18,406		$	11,110		$	8,921
As a percentage of average loans		0.58	%		0.24	%		0.25	%		0.17	%		0.16	%
Non-performing assets:
Non-accrual loans	$	146,867		$	65,174		$	24,443		$	52,204		$	33,179
Foreclosed assets		33,312			12,866			5,406			5,545			5,748
Total	$	180,179		$	78,040		$	29,849		$	57,749		$	38,927
As a percentage of:
Total loans and foreclosed assets		2.14	%		0.88	%		0.38	%		0.78	%		0.64	%
Total assets		1.11			0.52			0.22			0.44			0.33

⁽¹⁾ Shareholders’ equity excluding accumulated other comprehensive income (loss).

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