Exhibit 99.1

PRESS RELEASE

PacWest Bancorp

(NASDAQ: PACW)

PACWEST BANCORP ANNOUNCES RESULTS

FOR THE THIRD QUARTER OF 2011

—Net Earnings of $13.3 Million—

—Credit Loss Reserve at 3.34% of Net Non-Covered Loans and 161% of Non-Covered Nonaccrual Loans—

—Noninterest-Bearing Deposits at 36% of Total Deposits and Core at 77%—

—Net Interest Margin of 5.15%—

—Tangible Common Equity Increases by 6.5% or $29.5 Million—

Los Angeles, California . . . PacWest Bancorp (Nasdaq: PACW) today announced net earnings for the third quarter of 2011 of $13.3 million, or $0.36 per diluted share, compared to net earnings for the second quarter of 2011 of $12.8 million, or $0.35 per diluted share.

This press release contains certain non-GAAP financial disclosures for tangible common equity and pre-credit, pre-tax earnings.  The Company uses certain non-GAAP financial measures to provide meaningful supplemental information regarding the Company’s operational performance and to enhance investors’ overall understanding of such financial performance.  Given the use of tangible common equity amounts and ratios is prevalent among banking regulators, investors and analysts, we disclose our tangible common equity ratios in addition to equity-to-assets ratios.  Also, as analysts and investors view pre-credit, pre-tax earnings as an indicator of the Company’s ability to absorb credit losses, we disclose this amount in addition to net earnings.  Please refer to the table at the end of this release for a presentation of performance ratios in accordance with GAAP and a reconciliation of the non-GAAP financial measures to the GAAP financial measures.

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THIRD QUARTER RESULTS

(1)   FDIC loss sharing income and net covered OREO costs increased the third quarter 2011 efficiency ratio by 589 bps and reduced the second quarter 2011 efficiency ratio by 254 bps.

(2)   Non-covered loans exclude loans covered by loss sharing agreements with the FDIC.

The $463,000 increase in net earnings for the linked quarters was due to a lower provision for credit losses of $11.0 million ($6.4 million after tax), offset partially by lower net interest income of $4.2 million ($2.5 million after tax), lower FDIC loss sharing income of $4.4 million ($2.5 million after tax), and higher covered OREO costs of $3.6 million ($2.1 million after tax).

Net interest income declined due to lower accelerated accretion of discounts on covered loan payoffs and lower average loans, offset partially by higher interest income on investment securities from portfolio purchases and lower interest expense on deposits.  FDIC loss sharing income declined principally due to the lower provision for credit losses on covered loans.  Covered OREO costs increased due to higher write-downs in the current quarter, offset by higher gains on sales.

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Net credit costs on a pre-tax basis are shown in the following table:

The provision for credit losses for the third quarter had two components: $0 for non-covered loans and $348,000 for covered loans.  The third quarter non-covered credit loss provision of $0 was based on our allowance methodology which reflected (a) non-covered loan net charge-offs of $6.0 million, (b) the levels and trends of nonaccrual and classified loans, (c) the migration of loans into various risk classifications, and (d) a decline in outstanding non-covered loans.  During the third quarter, nonaccrual loans declined by $5.3 million to $60.0 million, classified loans decreased by $37.7 million to $177.7 million, and gross non-covered loans declined $19.4 million to $2.90 billion. The covered loan credit loss provision was driven by decreases in expected cash flows on covered loan pools compared to those previously estimated.  The covered loan credit loss provision and covered net OREO expense are offset partially by an increase in FDIC loss sharing income, which represents the FDIC’s share of these net costs. FDIC loss sharing income also includes reductions of the FDIC loss sharing asset when expected cash flows on covered loan pools improve.

Matt Wagner, Chief Executive Officer, commented, “We are pleased to post another profitable quarter with net earnings reaching $13.3 million for the third quarter and $36.8 million year-to-date.  We continue to generate significant core earnings, which strengthens our balance sheet, gives us operating flexibility, and enables us to take advantage of opportunities when they present themselves.”

Mr. Wagner continued, “Credit quality metrics continued to improve in the third quarter, with loan loss provisions, nonaccrual loans and classified loans all decreasing.  Our legacy credit loss reserve represented 3.34% of legacy loans and 161% of legacy nonaccruals at the end of September.  Although loan portfolio growth remains tepid, we are pleased that C&I loans increased $32 million during the quarter.  We continue to retain many maturing lending relationships that contribute positively to our profitability and net interest margin.”

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Vic Santoro, Executive Vice President and Chief Financial Officer, stated, “The Company had a sound third quarter, posting a continued strong net interest margin, lower overhead costs, improved credit metrics, ongoing deposit generation and a strong capital base.  Although our net interest margin declined during the quarter, at 5.15% it remains one of the highest in the nation.  Our third quarter loan yield was a respectable 6.87%, and all-in deposit cost dropped 5 basis points to 0.44%.  Operating costs continue to be controlled, demonstrated by a $1.6 million decline in noninterest expense when OREO costs are excluded.  The lower nonaccrual and classified loan levels we experienced in the third quarter translated into reduced credit loss provisions.  Core deposits were up almost $102 million, including a $29 million increase in non-interest bearing demand deposits.  The Company’s and the Bank’s capital positions remain well in excess of the well-capitalized regulatory minimums, and the Company’s tangible capital increased to $12.91 per share at September 30 compared to $12.12 at the end of June.”

YEAR TO DATE RESULTS

The higher net earnings for the nine months ended September 30, 2011 compared to the same period last year was due mostly to a lower provision for credit losses.  The provision for the prior year period included $71.4 million related to the Company’s sale of $323.6 million of non-covered classified loans in the first quarter of 2010; there was no similar sale of classified loans in the current year.   When compared to the same period for 2010, the current 2011 period shows higher net interest income of $18.1 million ($10.5 million after tax), lower provision for credit losses of $155.8 million ($90.4 million after tax), lower FDIC loss sharing income of $22.1 million ($12.8 million after tax), and lower noninterest expense of $3.0 million ($1.7 million after tax).  The increase in net interest income was due to (a) higher interest income on investment securities from purchases of $495.3 million during the current year-to-date period, (b) higher interest income on loans due to higher loan yield, and (c) lower interest expense on deposits from reduced pay rates.  The decline in noninterest expense reflects lower non-covered net OREO costs and insurance and assessment costs, offset by higher compensation and covered net OREO costs.

The comparability of financial information is affected by our acquisitions. Operating results include the operations of Los Padres Bank, which was acquired in August 2010 and added $824 million in assets and nine branch offices.

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BALANCE SHEET CHANGES

Total assets grew $99.2 million during the third quarter due to higher investment securities and interest-earning deposits in financial institutions, offset mostly by lower loans.  During the third quarter, investment securities available-for-sale grew $203.8 million due to purchases.  The non-covered loan portfolio declined $19.4 million on a gross basis, although this was net of a $32.1 million increase in commercial loans.  Excluding commercial loans, the loan portfolio continues to decline generally due to repayments, resolution activities, and low loan demand.  The covered loan portfolio declined $44.9 million.  At September 30, 2011, non-covered loans, net of unearned income, totaled $2.9 billion and the covered loan portfolio was $761.1 million.

Total deposits grew $67.9 million during the third quarter to $4.6 billion at September 30, 2011.  Time deposits decreased $33.7 million during the third quarter to $1.0 billion at September 30, 2011.  Core deposits, which include noninterest-bearing demand, interest checking, money market, and savings accounts, grew $101.6 million during the third quarter due to increases of $44.9 million, $28.8 million, and $20.9 million in money market deposits, noninterest-bearing demand deposits, and interest checking deposits, respectively.  At September 30, 2011, core deposits totaled $3.5 billion, or 77% of total deposits at that date.  Noninterest-bearing demand deposits were $1.6 billion at September 30, 2011 and represented 36% of total deposits at that date.

COVERED ASSETS

As part of the Los Padres and Affinity acquisitions we entered into loss sharing agreements with the FDIC that cover a substantial portion of losses incurred after the acquisition dates on covered loans and other real estate owned, and in the case of the Affinity acquisition, certain investment securities.

A summary of covered assets is shown in the following table as of the dates indicated:

NET INTEREST INCOME

Net interest income was $64.4 million for the third quarter of 2011 compared to $68.7 million for the second quarter of 2011.  The $4.3 million decline was due to a $4.7 million decrease in interest income, which was attributed to lower accelerated accretion of discounts on covered loan payoffs and lower average loans. Offsetting the decline in net interest income was a reduction in interest expense of $430,000 due to lower rates on money market deposits and a decline in average time deposits.

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Net interest income grew by $18.1 million to $198.9 million during the nine months ended September 30, 2011 compared to the same period last year.  This change was due to a $12.0 million increase in interest income and a $6.1 million decrease in interest expense.  The increase in interest income was due to purchases of investment securities and an increase in accelerated accretion of discounts on covered loan payoffs.  The decrease in interest expense was due to lower rates on money market deposits and lower average borrowing balances as $260 million of FHLB advances were repaid in the first half of 2010 and another $50 million were repaid in December 2010.

NET INTEREST MARGIN

Our net interest margin for the third quarter of 2011 was 5.15%, a decrease of 42 basis points from the 5.57% reported for the second quarter of 2011.  The decrease reflected lower accelerated accretion of discounts on covered loan payoffs and a shift in the mix of average interest-earning assets to lower yielding investment securities from higher yielding loans.  Average interest-earning assets increased $19.7 million for the linked quarters including a $162.8 million increase in average investment securities.

The net interest margin has been impacted by the accelerated accretion of discounts on covered loan payoffs and loans being placed on or removed from nonaccrual status.  The effects of such items on the net interest margin are shown in the following table:

The yield on average loans was 6.87% for the third quarter of 2011 compared to 7.18% for the prior quarter.  The  combination of accelerated accretion of discounts on covered loan payoffs and nonaccrual loan interest positively impacted the loan yield for the third quarter by 17 basis points and the second quarter by 52 basis points.  The cost of interest-bearing deposits declined six basis points to 0.69% and all-in deposit cost declined five basis points to 0.44% due to lower rates on money market deposits and lower average time deposits.

The net interest margin for the first nine months of 2011 was 5.35% compared to 4.95% for the same period last year.  The increase was due to a higher yield on loans, lower costs for money market deposits and subordinated debentures, and a lower average balance of FHLB advances, offset by lower average loans and an increase in the average balance of lower-yielding investment securities.

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NONINTEREST INCOME

Noninterest income for the third quarter of 2011 totaled $7.1 million compared to $11.2 million for the second quarter of 2011.  The $4.1 million decline was due to lower FDIC loss sharing income stemming from a lower provision for credit losses on covered loans.   FDIC loss sharing income also includes reductions of the FDIC loss sharing asset when the estimated amount of losses collectible from the FDIC decreases; this occurs when expected cash flows on covered loan pools improve during a reporting period causing the carrying value of the FDIC loss sharing asset to be reduced.

Noninterest income declined by $18.6 million to $23.2 million during the nine months ended September 30, 2011 compared to the same period last year.  This reduction was attributable to a decrease in FDIC loss sharing income.

NONINTEREST EXPENSE

Noninterest expense grew $2.1 million to $48.6 million during the third quarter of 2011 compared to $46.5 million for the second quarter of 2011.  This change was due to an increase in covered OREO costs.  Covered OREO costs increased by $3.6 million due to higher write-downs of $7.0 million, offset by higher gains on sales of $3.5 million.   Other expense declined $1.0 million due to director stock awards in the second quarter not repeated in the third quarter, write-downs of CRA investments in the second quarter also not repeated in the third quarter, and lower net loan collection expenses.

Noninterest expense includes amortization of time-based restricted stock, which is included in compensation, and intangible asset amortization.  Amortization of restricted stock totaled $2.1 million for each of the third and second quarters of 2011.  Intangible asset amortization totaled $2.0 million and $2.3 million for the third and second quarters of 2011, respectively.

Noninterest expense declined by $3.0 million to $136.5 million during the nine months ended September 30, 2011 compared to the same period last year.   This reduction was attributable to a decrease in non-covered OREO costs and lower insurance and assessments expense.  Non-covered OREO costs declined $5.9 million due to lower write-downs of $7.4 million, offset by lower gains on sales of OREO of $1.9 million.  The declines were offset by increases in almost all other expense categories for the additional operating costs arising from the Los Padres acquisition in August 2010.  Covered OREO costs increased by $1.7 million due to higher write-downs, offset by higher gains on sales of OREO.

Amortization of restricted stock totaled $6.2 million and $6.6 million for the nine months ended September 30, 2011 and 2010, respectively.  Intangible asset amortization totaled $6.6 million for the first nine months of 2011 compared to $7.3 million for the same period last year.

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CREDIT QUALITY

(1) Classified loans are those with a credit risk rating of substandard or doutbtful.

Credit Loss Provisions

The third quarter of 2011 provision for credit losses totaled $348,000 and was comprised of $0 on the non-covered loan portfolio and $348,000 on the covered loan portfolio.  The second quarter of 2011 provision for credit losses totaled $11.4 million and was composed of $5.5 million on the non-covered loan portfolio and $5.9 million on the covered loan portfolio.  The provision on the non-covered portfolio is generated by our allowance methodology and reflects net charge-offs, the levels of nonaccrual and classified loans, and the migration of loans into various risk classifications.  The provision for credit losses on the covered loans increases the covered loan allowance for credit losses and results from decreases in expected cash flows on covered loans compared to those previously estimated.  There has been an overall improvement in credit quality during the third quarter.

Third quarter of 2011 net charge-offs on non-covered loans totaled $6.0 million compared to second quarter net charge-offs of $7.2 million. The allowance for credit losses on the non-covered portfolio totaled $96.5 million and $102.6 million at September 30, 2011 and June 30, 2011, respectively, and represented 3.34% and 3.52% of the non-covered loan balances at those respective dates.  The allowance for credit losses as a percent of nonaccrual loans was 161% and 157% at September 30, 2011 and June 30, 2011, respectively.

Non-covered Nonaccrual Loans and Other Real Estate Owned

Non-covered nonperforming assets include non-covered nonaccrual loans and non-covered OREO and totaled $108.2 million at September 30, 2011 compared to $117.5 million at June 30, 2011.  The $9.3 million decline in non-covered nonperforming assets is due to reductions of $5.3 million and $4.0 million in nonaccrual loans and OREO, respectively.   The ratio of non-covered nonperforming assets to non-covered loans and non-covered OREO decreased to 3.68% at September 30, 2011 from 3.96% at June 30, 2011.

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The amount of new nonaccrual loans has slowed over the last several quarters as shown in the following chart:

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The following table presents the types and balances of non-covered loans included in the categories of nonaccrual and accruing loans past due between 30 and 89 days as of the dates indicated:

(1) Excludes covered loans.

The $5.3 million decline in non-covered nonaccrual loans during the third quarter was attributable to (a) foreclosures of $2.4 million, (b) other reductions, payoffs and returns to accrual status of $5.7 million, (c) charge-offs of $6.0 million, and (d) additions of $8.8 million.

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Below is a summary of the ten largest lending relationships on nonaccrual status, excluding SBA-related loans, at September 30, 2011:

(1) On nonaccrual status at June 30, 2011 

The following table presents the details of non-covered and covered OREO as of the dates indicated:

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The following table presents non-covered and covered OREO activity for the third quarter:

(1) Represent amounts due to participants and for guarantees, property taxes or any other prior lien positions.

REGULATORY CAPITAL MEASURES ARE ABOVE THE WELL-CAPITALIZED MINIMUMS

PacWest and its wholly-owned banking subsidiary, Pacific Western Bank, each remained well capitalized at September 30, 2011 as shown in the following table.

ABOUT PACWEST BANCORP

PacWest Bancorp (“PacWest”) is a bank holding company with $5.5 billion in assets as of September 30, 2011, with one wholly-owned banking subsidiary, Pacific Western Bank (“Pacific Western”). Through 77 full-service community banking branches, Pacific Western provides commercial banking services, including real estate, construction and commercial loans, to small and medium-sized businesses. Pacific Western’s branches are located in Los Angeles, Orange, Riverside, San Bernardino, Santa Barbara, San Diego, San Francisco, San Luis Obispo, San Mateo and Ventura Counties in California and Maricopa County in Arizona.  Through its subsidiary BFI Business Finance and its division First Community Financial, Pacific Western also provides working capital financing to growing companies located throughout the Southwest, primarily in the states of Arizona, California and Texas. Additional information regarding PacWest Bancorp is available on the Internet at www.pacwestbancorp.com.  Information regarding Pacific Western Bank is also available on the Internet at www.pacificwesternbank.com.

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FORWARD-LOOKING STATEMENTS

This press release contains certain forward-looking information about PacWest that is intended to be covered by the safe harbor for “forward-looking statements” provided by the Private Securities Litigation Reform Act of 1995. All statements other than statements of historical fact are forward-looking statements. Such statements involve inherent risks and uncertainties, many of which are difficult to predict and are generally beyond the control of the Company. We caution readers that a number of important factors could cause actual results to differ materially from those expressed in, implied or projected by, such forward-looking statements. Risks and uncertainties include, but are not limited to: lower than expected revenues; credit quality deterioration or a reduction in real estate values could cause an increase in the allowance for credit losses and a reduction in net earnings; increased competitive pressure among depository institutions; the Company’s ability to complete future acquisitions, successfully integrate such acquired entities, or achieve expected beneficial synergies and/or operating efficiencies within expected time-frames or at all; settlements with the FDIC related to our loss-sharing arrangement and other adjustments related to the Los Padres Bank and Affinity Bank acquisitions; the possibility that personnel changes will not proceed as planned; the cost of additional capital is more than expected; a change in the interest rate environment reduces net interest margins; asset/liability repricing risks and liquidity risks; pending legal matters may take longer or cost more to resolve or may be resolved adversely to the Company; general economic conditions, either nationally or in the market areas in which the Company does or anticipates doing business, are less favorable than expected; environmental conditions, including natural disasters, may disrupt our business, impede our operations, negatively impact the values of collateral securing the Company’s loans or impair the ability of our borrowers to support their debt obligations; the economic and regulatory effects of the continuing war on terrorism and other events of war, including the conflicts in the Middle East; legislative or regulatory requirements or changes adversely affecting the Company’s business; changes in the securities markets; regulatory approvals for any capital activities cannot be obtained on the terms expected or on the anticipated schedule; and, other risks that are described in PacWest’s public filings with the U.S. Securities and Exchange Commission (the “SEC”). If any of these risks or uncertainties materializes or if any of the assumptions underlying such forward-looking statements proves to be incorrect, PacWest’s results could differ materially from those expressed in, implied or projected by such forward-looking statements. PacWest assumes no obligation to update such forward-looking statements.

For a more complete discussion of risks and uncertainties, investors and security holders are urged to read PacWest Bancorp’s annual report on Form 10-K, quarterly reports on Form 10-Q and other reports filed by PacWest with the SEC.  The documents filed by PacWest with the SEC may be obtained at PacWest Bancorp’s website at www.pacwestbancorp.com or at the SEC’s website at www.sec.gov.  These documents may also be obtained free of charge from PacWest by directing a request to: PacWest Bancorp c/o Pacific Western Bank, 275 North Brea Boulevard, Brea, CA 92821.  Attention: Investor Relations. Telephone 714-671-6800.

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PACWEST BANCORP AND SUBSIDIARIES

CONDENSED CONSOLIDATED BALANCE SHEETS

(Unaudited)

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PACWEST BANCORP AND SUBSIDIARIES

CONDENSED CONSOLIDATED STATEMENTS OF EARNINGS (LOSS)

(Unaudited)