Exhibit 99.1

FOR IMMEDIATE RELEASE:

Guaranty Bancorp Announces 2011 Annual and Fourth Quarter Financial Results

·                  Net income rose for the fourth consecutive quarter

·                  Net loans grew in the fourth quarter despite continued reductions in nonperforming loans

·                  Adversely classified assets declined by 50.5% through 2011

·                  Net interest margin improvement of 24 basis points on a linked quarter basis to 3.86%

·                  Tangible common equity rose to 9.6% of tangible assets at 12/31/2011 while book equity increased to 10.1% of total assets

DENVER, January 25, 2012 — Guaranty Bancorp (Nasdaq: GBNK), a Colorado-based, community bank holding company, today reported fourth quarter 2011 net income of $2.3 million, or $0.02 earnings per basic and diluted common share, compared to a fourth quarter 2010 net loss of $22.6 million, or $0.44 loss per basic and diluted common share, including the effect of preferred stock dividends.

Paul W. Taylor, Guaranty Bancorp’s President and Chief Executive Officer, stated, “We are pleased with our accomplishments in 2011, as demonstrated by significant improvements in the key operating metrics of our Company. We finished 2011 with net income of $6.4 million, while substantially improving our asset quality. Our asset quality ratio of classified assets to Tier 1 capital and allowance fell to 36.6% at the end of the fourth quarter 2011 as compared to 74.2% at end of the prior year, due to a 50.5% decline in adversely classified assets in 2011.”

Mr. Taylor continued, “In addition, we grew our loan portfolio in the fourth quarter by $9.8 million, furthering our investment in local Colorado companies. From the prior year, our core deposit balances grew by 12.2%, while high-cost time deposits declined by 56.9%. In addition, the early conversion of our preferred stock in the third quarter of this year positively impacted several of our key capital ratios. Our leverage ratio improved to 12.1% at December 31, 2011 as compared to 6.2% at the end of the prior year and our tangible common equity ratio increased to 9.6% at December 31, 2011 as compared to 4.3% at the end of the prior year. Our total equity ratio increased to 10.1% from 8.6% during the same period.”

For the year ended December 31, 2011, net income was $6.4 million, compared to a net loss of $31.3 million for the year ended December 31, 2010. The earnings per common share calculation for the year 2011 included a non-cash adjustment of approximately $19.8 million, or $0.30 per basic and diluted common share, related to the regular quarterly paid-in-kind dividends on the Company’s Series A Convertible Preferred Stock of $4.6 million and the accelerated conversion of

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the Series A Convertible Preferred Stock into common stock of $15.2 million. After giving effect to the preferred stock dividends and mandatory accelerated conversion of the preferred stock, the loss per basic and diluted common share was $0.21 for the year ended December 31, 2011.  For the same period in 2010, the loss per basic and diluted common share was $0.72, including the effect of preferred stock dividends. The improvement in net income is due to a $29.4 million reduction in provision for loan losses, due to lower levels of charge-offs and improved asset quality in 2011, a $13.2 million reduction in noninterest expense, mostly due to lower expenses related to other real estate owned in 2011, and a $5.8 million increase in noninterest income, due to higher net gains on sales of investments in 2011, as well as an other-than-temporary impairment loss recognized in 2010. These improvements were partially offset by a $6.3 million decrease in income tax benefit and a $4.5 million decrease in net interest income, due to a reduced level of earning assets in 2011.

Key Financial Measures

Income Statement

Balance Sheet

Net Interest Income and Margin

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Fourth quarter 2011 net interest income of $15.3 million increased by $0.2 million compared to the third quarter 2011, and was relatively flat from the fourth quarter 2010. The Company’s net interest margin of 3.86% for the fourth quarter 2011 reflected an increase of 24 basis points from the third quarter 2011 and an increase of 47 basis points from the fourth quarter 2010.

In the fourth quarter 2011, interest income and interest expense decreased by $0.7 million and $0.9 million, respectively, from the prior quarter, resulting in an increase in net interest income of $0.2 million. The decline in interest income was due to a reduced level of average earning assets, while the decrease in interest expense was due to the early payoff of $51.0 million of Federal Home Loan Bank (FHLB) term notes and a $56.9 million decrease in average time deposits, mostly higher-cost, brokered time deposits. At December 31, 2011, our remaining brokered deposit is $10.2 million which will mature in March 2012.

Net interest income was relatively flat in the fourth quarter 2011, as compared to the same quarter in 2010, due to a decline in interest income of $2.8 million, offset by an equal decline in interest expense. The decline in interest income was primarily due to an unfavorable volume variance of $2.7 million and a slight unfavorable rate variance of $0.2 million. The unfavorable volume variance was due mostly to the $173.4 million decrease in average loan balances. The decline in interest expense is due to a favorable volume variance of $1.4 million, in addition to a favorable rate variance of $1.4 million. These favorable volume and rate variances are a result of a $309.7 million reduction in higher-cost average time deposits and the prepayment of $51.0 million in FHLB term notes bearing an average cost of 3.5%. Despite a relatively flat variance in net interest income comparatively, overall net interest margin improved by 47 basis points to 3.86% in the fourth quarter 2011 as compared to 3.39% in the same quarter in 2010.

During 2011, net interest income decreased by $4.5 million, from $64.4 million in 2010 to $59.9 million. Interest income in 2011 was $13.6 million lower than in 2010 due to an unfavorable volume variance of $11.5 million, in addition to a $2.1 million unfavorable rate variance. The unfavorable volume variance was due to a $256.3 million decline in average loan balances, partially offset by a $61.0 million increase in the average balance of all other earning assets, mostly investment securities. The unfavorable rate variance was due to $2.7 million decline in loan income, partially offset by a $0.6 million increase in investment income. The decline in interest income was partially offset by the decrease in interest expense of $9.2 million. This decrease was the result of a favorable volume variance of $5.0 million and a favorable rate variance of $4.2 million. These favorable variances are due to reductions in high-cost, time deposits of $299.9 million and prepayments of FHLB notes, discussed above. Although net interest income declined in 2011 compared to 2010, overall net interest margin increased 14 basis points from 3.47% in 2010 to 3.61% in 2011.

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Noninterest Income

The following table presents noninterest income as of the dates indicated:

The $2.7 million decrease in noninterest income in the fourth quarter 2011 as compared to the third quarter 2011 reflects a $2.7 million change in gain on sale of securities from the $3.0 million gain recognized in the third quarter to the $0.3 million gain recognized in the fourth quarter. The gain in the third quarter was due to the sale of several mortgage-backed securities, based on the expectation that these securities were expected to have significant increases in prepayment speeds. The gain recognized in the fourth quarter was due to the sale of a single adjustable rate agency security. Non-interest income increased $3.4 million in the fourth quarter 2011 as compared to the fourth quarter 2010. This variance is primarily due to a $3.5 million other-than-temporary impairment on a single, local, non-rated municipal bond that was recognized in the fourth quarter 2010.

Noninterest income increased $5.8 million from $8.1 million in 2010 to $13.9 million in 2011. This variance is attributable to the $3.4 million increase in net gains on sales of securities year over year, as well as the net impact of two 2010 transactions. These transactions consisted of a $3.5 million other-than-temporary impairment on a single, local, non-rated bond, as discussed above, offset by a $1.2 million gain on sale of loans.  Additionally, customer service and other fees increased by $0.2 million year over year, primarily as a result of higher overdraft and interchange fee income.

Noninterest Expense

The following table presents noninterest expense as of the dates indicated:

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The $2.6 million decrease in noninterest expense in the fourth quarter 2011 as compared to the third quarter 2011 is due mostly to a $2.7 million prepayment penalty on the early payoff of $51.0 million FHLB term notes. Other variances include increases in salaries and benefits of $0.3 million and net other real estate owned expenses of $0.2 million, offset by decreases in insurance and assessments of $0.2 million, and other professional expenses of $0.3 million. The increase in salary and benefit expense is due to higher claims related to our self-insured medical plan and the increase in net other real estate expense is due to lower operating income related to a single property. The decrease in insurance and assessments is due to lower insurance premiums related to the annual renewal of our insurance policies. In addition, professional fees decreased due to costs incurred in the third quarter related to our special shareholder meeting and preferred stock conversion.

Noninterest expense decreased $1.6 million to $14.8 million in the fourth quarter 2011 from $16.4 million in the same period in 2010. Net expenses related to other real estate owned contributed to the largest portion of this variance with a decline of $1.0 million. Other declines were realized in insurance and assessments of $0.5 million, mostly due to lower FDIC assessments of $0.4 million.

Noninterest expense declined $13.2 million to $62.5 million in 2011 from $75.7 million in 2010, primarily due to a $13.4 million decrease in expenses related to other real estate owned. This decrease is due to a reduction in net write-downs resulting from valuation adjustments and sales, as well as a reduced level of net operating expenses related to these properties. In addition to these declines, insurance and assessment expense decreased $2.5 million, mostly due to lower FDIC assessments, and amortization of intangible assets decreased $1.1 million based on an accelerated amortization schedule. Partially offsetting these reductions in expenses were prepayment penalties of $2.7 million related to the early payoff of high-cost, FHLB term notes, increases in other general and administrative expenses of $0.7 million related to increases in advertising and business development of $0.5 million, and increases in other professional fees of $0.4 million. The decrease in FDIC assessment expense for 2011 as compared to 2010 is due primarily to a favorable change in our risk classification in the third quarter 2010 as well as the implementation of new rules mandated by the Dodd-Frank Wall Street Reform and Consumer Protection Act. These new rules changed the assessment base from total deposits to average total assets less tangible capital, but also significantly lowered the assessment rates, causing a net favorable impact on our FDIC insurance premiums.

At December 31, 2011, our income tax valuation allowance was approximately $6.6 million, compared to $8.5 million at December 31, 2010 and $7.4 million at September 30, 2011.  In assessing the realization of deferred tax assets, management evaluates both positive and negative evidence, including the existence of any cumulative losses in the current year and the prior two years, the amount of taxes paid in available carry-back years, the forecasts of future income, taking into account applicable tax planning strategies, and assessments of current and future economic and business conditions.  This analysis is updated quarterly and adjusted as necessary.  In 2010, based on various tax planning strategies, the Company recorded a partial valuation allowance for deferred tax assets in the amount of $8.5 million. Based upon the updated quarterly analysis at December 31, 2011, this partial valuation allowance was reduced from $7.4 million as of September 30, 2011 to $6.6 million as of December 31, 2011.

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Balance Sheet

At December 31, 2011, the Company had total assets of $1.7 billion, which represented a $2.7 million decline as compared to September 30, 2011 and a $180.4 million decline as compared to December 31, 2010. The decline in assets from September 30, 2011 consists primarily of a $89.2 million decline in securities sold, not yet settled, partially offset by an increase in cash and due from bank balances of $16.0 million, an increase in investments of $71.7 million, and an increase in loans, net of unearned discount, of $9.8 million. The decline in total assets year over year is primarily due to a decline in loans, net of unearned discount, of $106.4 million. The decrease in loans is primarily due to a $127.2 million decline in commercial loans, partially offset by an increase in residential and commercial real estate loans of $50.2 million. In addition, investments decreased by $32.5 million and cash and due from bank balances decreased by $32.2 million.

In the fourth quarter 2011, our loans held for investment, net of unearned discount, increased by $9.8 million. Residential and commercial real estate loans increased by $36.1 million, partially offset by declines in commercial loans of $14.0 million, construction loans of $6.5 million,  equity lines of credit of $2.4 million and consumer installment loans of $1.6 million. At December 31, 2011, our residential and commercial real estate portfolio consisted of 33.6% owner occupied properties and 6.6% multi-family properties. In addition to the net growth in our overall loan portfolio during the fourth quarter, our pipeline for new loan opportunities has continued to grow each month.

The following table sets forth the amounts of our loans outstanding (excluding loans held for sale) at the dates indicated:

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Since December 31, 2010, the ratio of construction, land and land development loans to capital fell by 33 percentage points to 52% at December 31, 2011. Similarly, the ratio of commercial real estate loans to capital fell by 39 percentage points to 254% at December 31, 2011. These concentration ratios are below the regulatory commercial real estate concentration guidelines of 100% for land and construction loans and 300% for all investor real estate loans, respectively.

The following table sets forth the amounts of our deposits outstanding at the dates indicated:

Noninterest-bearing deposits as a percentage of total deposits increased to 34.3% at December 31, 2011, as compared to 25.6% at December 31, 2010.

Non-maturing deposits at December 31, 2011 increased by $121.0 million as compared to December 31, 2010 and increased by $24.9 million compared to September 30, 2011. The increase in interest-bearing demand and NOW accounts and offsetting decline in money market accounts in the fourth quarter 2011 is primarily due to a change in the type of account used for our cash sweep product. The decision to utilize an interest-bearing demand account rather than a money market account for our sweep product was based on our ability to deliver a nearly identical sweep product with a less restrictive account type.

Time deposits continue to decrease primarily as a result of management’s efforts to reduce the overall level of higher cost time deposits, particularly brokered and internet deposits. Total brokered deposits at December 31, 2011 were $10.2 million as compared to $179.9 million at December 31, 2010. Brokered deposits represented 0.8% of total deposits at December 31, 2011 as compared to 12.2% at December 31, 2010. In addition to this $169.7 million decline in brokered deposits over the past twelve months, we also experienced a $28.6 million decline in internet time deposits over the same time period. The remaining decline in time deposits is primarily related to the non-renewal of other higher cost certificates of deposits. Management monitors time deposit maturities and renewals on a daily basis and our current retention ratio is in excess of 60.0%.

Borrowings were $110.2 million at December 31, 2011 as compared to $110.2 million at September 30, 2011 and $163.2 million at December 31, 2010. The Company elected to payoff $51 million of FHLB term notes in September 2011. The weighted average rate of these advances was 3.5% with maturity dates that ranged from November 2011 to February 2014. The entire balance of borrowings at each balance sheet date consists of term notes with the FHLB.

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Regulatory Capital Ratios

All of the Company’s and our subsidiary bank’s regulatory capital ratios are above the highest regulatory capital threshold of “well-capitalized” at December 31, 2011. The Company’s and our subsidiary bank’s actual capital ratios for December 31, 2011 and December 31, 2010 are presented in the table below:

The improvements in the consolidated Tier 1 risk-based capital ratio and leverage ratio are primarily attributable to the mandatory accelerated conversion of preferred stock in the third quarter 2011. In prior periods, the preferred stock was treated for Tier 1 capital purposes as a restricted core capital element limited to 25% of total Tier 1 capital. Post-conversion, the newly converted common stock is treated as an unrestricted core capital element, which significantly improves our Tier 1 and leverage ratios.

Generally, the allowance for loan losses is included in total capital for regulatory purposes; however, it is limited to 1.25% of total risk-weighted assets. At December 31, 2011, approximately $17.8 million of the subsidiary bank’s allowance for loan losses was disallowed from being included in total risk-based capital under the regulatory capital rules, or approximately 1.32% of our consolidated risk-weighted assets. No deferred tax assets were disallowed for purposes of computing consolidated Tier 1 capital due to increases in consolidated Tier 1 capital.

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Asset Quality

The following table presents select asset quality data (including loans held for sale) as of the dates indicated:

(1)Past due loans include both loans that are past due with respect to payments and loans that are past due because the loan has matured, and are in the process of renewal, but continue to be current with respect to payments.

(2) Excludes loans held for sale.

The following table summarizes our past due loans by class (including loans held for sale) as of the dates indicated:

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During the fourth quarter 2011, nonaccrual loans decreased by $19.0 million and other classified loans decreased by $0.6 million. The decrease in nonaccrual loans is mostly due to the transfer of a loan held for sale in the amount of $14.2 million to other real estate owned, due to the foreclosure of the property. Other real estate owned increased by $7.0 million compared to the prior quarter due to the aforementioned transfer of the loan held for sale into other real estate owned, offset by the sale of a hotel for $7.0 million. The remaining decline in nonaccrual loans of $4.8 million is due to loan payments, net of new additions. Loans classified as special mention or watch increased by $1.6 million mostly due to the downgrade of a single loan in the amount of $4.7 million.

As compared to December 31, 2010, our nonaccrual loans have declined 69.7% from $88.5 million to $26.8 million at December 31, 2011. The decrease in nonaccrual loans is the result of management’s successful efforts to work through and dispose of our problem loans. Other real estate owned has increased by $6.1 million, mostly due to the transfer from loans held for sale discussed above. Loans classified as special mention or watch decreased by $28.1 million from $128.9 million at December 31, 2010 to $100.8 million at December 31, 2011.

Net charge-offs in the fourth quarter 2011 were $2.2 million as compared to $4.0 million in the third quarter 2011 and $14.3 million in the fourth quarter 2010. Net charge-offs in 2011 decreased by $21.9 million from $39.3 million in 2010 to $17.4 million in 2011.

The general component of the allowance for loan losses decreased from $31.4 million at September 30, 2011 to $31.2 million at December 31, 2011. The general component represented 2.8% of loans, net of unearned discount, at December 31, 2011 as compared to 2.9% of loans, net of unearned discount, at the end of the previous quarter.  The coverage ratio, defined as nonaccrual loans divided by total allowance, has improved from 60.6% at year end 2010, to 129.3% at December 31, 2011.

The Company recorded a provision for loan losses in the fourth quarter 2011 of $1.0 million, as compared to $1.0 million in the third quarter 2011 and $19.5 million in the fourth quarter 2010. In 2011, the provision for loan loss was $5.0 million, which was $29.4 million less than the provision for 2010 of $34.4 million. The lower level of provision for loan loss over the last year reflects the reduction of outstanding balances in our loan portfolio combined with overall improvement in asset quality and lower levels of charge-offs.

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Shares Outstanding

As of December 31, 2011, the Company had 105,436,623 shares of common stock outstanding, consisting of 100,341,623 shares of voting common stock and 5,095,000 shares of non-voting common stock. At December 31, 2011, total common shares outstanding include 1,546,292 shares of unvested stock awards. In connection with the termination of the Company’s deferred compensation plan, 156,567 shares of voting common stock held by the plan were distributed to participants as of December 15, 2011.

Non-GAAP Financial Measures

This press release includes non-GAAP financial measures related to tangible assets, including tangible book value, tangible book value after giving effect to conversion of preferred stock, and tangible equity ratio, all of which exclude intangible assets.

The Company discloses these non-GAAP financial measures to provide meaningful supplemental information regarding the Company’s operational performance and to enhance investors’ overall understanding of the Company’s core financial performance. Management believes that these non-GAAP financial measures allow for additional transparency and are used by some investors, analysts and other users of the Company’s financial information as performance measures. These non-GAAP financial measures are presented for supplemental informational purposes only and should not be considered a substitute for financial information presented in accordance with GAAP. These non-GAAP financial measures presented by the Company may be different from non-GAAP financial measures used by other companies.

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The following non-GAAP schedules reconcile the book value per share to the tangible book value per share and the GAAP equity ratio to the tangible equity ratio as of the dates indicated:

Tangible Common Equity Ratio

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About Guaranty Bancorp

Guaranty Bancorp is a bank holding company that operates 34 branches in Colorado through a single bank, Guaranty Bank and Trust Company. The bank provides banking and other financial services including commercial and industrial, real estate, construction, energy, consumer and agricultural loans throughout its targeted Colorado markets to consumers and small to medium-sized businesses, including the owners and employees of those businesses. The bank also provides private banking and trust services, including personal trust administration, estate settlement, investment management accounts and self-directed IRAs. More information about Guaranty Bancorp can be found at www.gbnk.com.

Forward-Looking Statements

This press release contains forward-looking statements, which are included in accordance with the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995. In some cases, you can identify forward-looking statements by terminology such as “may,” “will,” “should,” “could,” “expects,” “plans,” “intends,” “anticipates,” “believes,” “estimates,” “predicts,” “potential,” or “continue,” or the negative of such terms and other comparable terminology. These forward-looking statements involve known and unknown risks, uncertainties and other factors that may cause the Company’s actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by such forward-looking statements. Such factors include, among others, the following: failure to maintain adequate levels of capital and liquidity to support Company’s operations; the effect of the regulatory written agreement the Company and its bank subsidiary have entered into and potential future supervisory action against the Company or its bank subsidiary; general economic and business conditions in those areas in which the Company operates; demographic changes; competition; fluctuations in interest rates; continued ability to attract and employ qualified personnel; ability to receive regulatory approval for our bank subsidiary to declare dividends to the Company; adequacy of our allowance for loan losses, changes in credit quality and the effect of credit quality on our provision for credit losses and allowance for loan losses; changes in governmental legislation or regulation, including, but not limited to, any increase in FDIC insurance premiums; changes in accounting policies and practices; changes in the deferred tax asset valuation allowance; changes in business strategy or development plans; changes in the securities markets; changes in consumer spending, borrowing and savings habits; the availability of capital from private or government sources; competition for loans and deposits and failure to attract or retain loans and deposits; changes in the financial performance and/or condition of our borrowers and the ability of our borrowers to perform under the terms of their loans and other terms of credit agreements; political instability, acts of war or terrorism and natural disasters; and additional “Risk Factors” referenced in the Company’s most recent Annual Report on Form 10-K filed with the Securities and Exchange Commission, as supplemented from time to time. When relying on forward-looking statements to make decisions with respect to the Company, investors and others are cautioned to consider these and other risks and uncertainties. The Company can give no assurance that any goal or plan or expectation set forth in forward-looking statements can be achieved and readers are cautioned not to place undue reliance on such statements, which speak only as of the date made. The forward-looking statements are made as of the date of this press release, and the Company does not intend, and assumes no obligation, to update the forward-looking statements or to update the reasons why actual results could differ from those projected in the forward-looking statements.

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GUARANTY BANCORP AND SUBSIDIARIES

Unaudited Consolidated Balance Sheets