Exhibit 99.1

PRESS RELEASE

PacWest Bancorp

(Nasdaq: PACW)

PACWEST BANCORP ANNOUNCES RESULTS

FOR THE FOURTH QUARTER AND FULL YEAR 2017

Fourth Quarter 2017 Highlights

·                  CU Bancorp (“CUB”) Acquisition Closed October 20, 2017

·                  Sold $1.5 Billion of Cash Flow Loans

·                  Net Earnings of $84.0 Million, or $0.66 Per Diluted Share

·                  New Loan and Lease Production of $1.6 Billion and Annualized Growth Excluding Acquired and Sold Loans of 17%

·                  Classified Loans and Leases Reduced by 19%

·                  Tax Benefit of $1.2 Million from Enactment of Tax Cuts and Jobs Act

Full Year 2017 Highlights

·                  Net Earnings of $357.8 Million, or $2.91 Per Diluted Share

·                  New Loan and Lease Production of $4.7 Billion and Growth Excluding Acquired and Sold Loans of 7%

·                  Core Deposits Growth of $3.4 Billion, Including $2.7 Billion from CUB Acquisition

·                  Tax Equivalent Net Interest Margin of 5.10%

·                  Classified Loans and Leases Reduced by 32%

Los Angeles, California . . . PacWest Bancorp (Nasdaq: PACW) today announced net earnings for the fourth quarter of 2017 of $84.0 million, or $0.66 per diluted share, compared to net earnings for the third quarter of 2017 of $101.5 million, or $0.84 per diluted share.  Net earnings for the full year 2017 were $357.8 million, or $2.91 per diluted share, compared to net earnings for the full year 2016 of $352.2 million, or $2.90 per diluted share.

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The decrease in net earnings from the prior quarter was due primarily to higher noninterest expense, higher income tax expense and lower noninterest income offset by higher net interest income and a lower provision for credit losses.  Noninterest expense for the fourth quarter of 2017 was higher mainly due to an increase in acquisition, integration and reorganization costs of $14.6 million related to the CUB acquisition and integration. Income tax expense for the fourth quarter of 2017 was higher as the third quarter of 2017 reflected a $13.6 million reversal of a valuation allowance related to tax credits, while the fourth quarter reflected a $2.0 million increase in the valuation allowance. Noninterest income for the fourth quarter of 2017 declined mainly due to the tax-related decision to sell certain securities resulting in a loss for the quarter of $3.3 million.

Matt Wagner, President and CEO, commented, “Although the fourth quarter included several significant items, the benefits of the CUB acquisition for our future profitability were apparent in our fourth quarter results. Interest income on loans and leases increased 10% over the prior quarter, core deposits increased to 85% of total deposits, and the CUB integration as well as the vast majority of cost save initiatives were achieved in December. We are on track to achieve the remainder of our targeted expense savings during the first quarter of 2018.”

Mr. Wagner continued, “Our organic loan growth of $684 million in the fourth quarter was the strongest of the year. The fourth quarter sale of $1.5 billion in cash flow loans and the exit from the CapitalSource Division origination operations related to general, technology, and healthcare cash flow loans allows us to focus on profitably growing our other businesses.”

Mr. Wagner added, “The strong fourth quarter capped a year of profitable growth and continued our solid operating performance resulting in a 2017 return on assets of 1.58% and return on tangible equity of 15.15%. These outstanding operating results allowed us to return $347 million to our stockholders in 2017 through stock repurchases and dividends, including $100 million of stock repurchases in the fourth quarter.”

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FINANCIAL HIGHLIGHTS

(1) The operations of CU Bancorp are included from its October 20, 2017 acquisition date.

(2) Non-GAAP measure.

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INCOME STATEMENT HIGHLIGHTS

Net Interest Income

Net interest income increased by $21.3 million to $263.0 million for the fourth quarter of 2017 compared to $241.7 million for the third quarter of 2017 due mainly to higher average loan and lease balances primarily from the CUB acquisition. The loan and lease yield was 5.89% for the fourth quarter of 2017 compared to 6.01% for the third quarter of 2017.  The decrease in the loan and lease yield was principally due to a lower yield on the acquired CUB loans, offset partially by an increase in discount accretion on acquired loans.  Total discount accretion on acquired loans was $6.8 million for the fourth quarter of 2017 (15 basis points on the loan and lease yield) compared to $5.5 million for the third quarter of 2017 (14 basis points on the loan and lease yield). A total discount of $37.0 million was recorded in connection with the acquired CUB loan portfolio, of which $2.9 million was accreted during the fourth quarter. The total remaining acquired loan discount as of December 31, 2017 was $56.9 million.

The tax equivalent NIM was 4.97% for the fourth quarter of 2017 compared to 5.08% for the third quarter of 2017.  The decrease in the NIM was mostly due to the lower yield on the CUB loans and securities and a higher cost of average interest-bearing liabilities, offset partially by the increase in discount accretion on acquired loans.  Total discount accretion on acquired loans contributed 13 basis points to the NIM for the fourth quarter of 2017 and 11 basis points for the third quarter of 2017.

The cost of average total deposits decreased to 0.30% for the fourth quarter of 2017 from 0.31% for the third quarter of 2017 due to the lower cost of the deposits acquired from CUB.

Noninterest Income

Noninterest income decreased by $4.6 million to $26.8 million for the fourth quarter of 2017 compared to $31.4 million for the third quarter of 2017 due mainly to a $4.6 million decrease in the gain on sale of securities. In light of the reduction in the statutory federal income tax rate effective January 1, 2018, we sold approximately $173 million of securities during the fourth quarter of 2017 resulting in a realized loss for the quarter of $3.3 million. The proceeds will be reinvested into higher yielding securities that are expected to recoup the realized loss in approximately one year. In addition, dividends and gains on equity investments decreased by $1.5 million and service charges on deposit accounts increased by $1.1 million primarily due to the increased number of accounts from the CUB acquisition.

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The following table presents details of noninterest income for the periods indicated:

Noninterest Expense

Noninterest expense increased by $24.3 million to $142.9 million for the fourth quarter of 2017 compared to $118.5 million for the third quarter of 2017 due mostly to an increase in acquisition, integration and reorganization costs of $14.6 million related to the CUB acquisition and integration.  Almost all operating expense categories were higher quarter over quarter due mainly to the CUB acquisition. Compensation expense also includes $2.9 million for separation costs in connection with exiting the origination operations related to general, technology, and healthcare cash flow loans. Intangible asset amortization increased $2.0 million as a result of the CUB acquisition partially offset by scheduled reductions in amortization for previous acquisitions. The intangible asset amortization for 2018 is expected to be approximately $24 million. During the fourth quarter of 2017, a foreclosed property that represented approximately 90% of the total foreclosed property balance was sold for a nominal gain. This property was subject to a valuation write-down of $2.1 million in the third quarter of 2017.

The following table presents details of noninterest expense for the periods indicated:

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Income Taxes

The overall effective income tax rate was 40.2% for the fourth quarter of 2017 and 27.2% for the third quarter of 2017.  The effective tax rate for the fourth quarter of 2017 was higher mainly due to the fourth quarter tax provision including a $2.0 million increase in the foreign tax credit valuation allowance due to the sale of certain foreign loans, whereas the prior quarter included a $13.6 million reversal of a valuation allowance related to foreign tax credits which were deemed more likely than not to be utilized before they expire. The fourth quarter tax provision also included $2.4 million of income tax expense related to non-deductible merger costs and other adjustments offset by a $1.2 million benefit from remeasuring the deferred federal tax assets and liabilities as a result of the Tax Cuts and Jobs Act. This adjustment to deferred federal tax liabilities is management’s best estimate based on the information available as of this earnings release and is subject to change as final tax calculations are completed in conjunction with the filing of the Form 10-K. The effective tax rate for the full year 2017 was 35.5%. While the analysis on the impact of the Tax Cuts and Jobs Act is still ongoing at this time, we expect the 2018 effective tax rate to be in the range of 27% to 29%.

BALANCE SHEET HIGHLIGHTS

Loans and Leases

Total loans and leases held for investment, net of deferred fees, increased by $1.3 billion in the fourth quarter of 2017 to $17.0 billion at December 31, 2017.  The net increase was driven mainly by the acquisition of CUB loans of $2.1 billion, fourth quarter new production of $1.6 billion, and disbursements of $724 million, partially offset by loan sales of $1.0 billion, payoffs of $729 million, paydowns of $813 million, and transfers to loans held for sale of $481 million.  For the year ended December 31, 2017, loans and leases held for investment, net of deferred fees, increased by $1.5 billion. Excluding the effect of the acquired CUB loans and the two portfolio sales in 2017, the annualized loan growth rate for the fourth quarter of 2017 was 17% and the growth rate for the full year 2017 was 7%.

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The following table presents a roll forward of loans and leases held for investment, net of deferred fees, for the periods indicated:

(1)         Includes direct financing leases but excludes equipment leased to others under operating leases.

(2)         Sales for the three months ended December 31, 2017 exclude loans held for sale of $481.1 million at December 31, 2017. Sales for the three months ended September 30, 2017 exclude sales of loans that were transferred to loans held for sale of $175.2 million at June 30, 2017.

(3)         The weighted average rate on new production presents contractual rates and does not include amortized fees. Amortized fees added approximately 30 basis points to loan yields in 2017.

Cash Flow Loan Sale

During the fourth quarter of 2017, the Company sold $1.5 billion of cash flow loans, of which none were on nonaccrual and $4.7 million were classified, and exited its CapitalSource Division origination operations related to general, technology, and healthcare cash flow loans.  These actions were taken to lower the Company’s credit risk profile and improve its funding mix by allowing the majority of our wholesale deposits to run off. As of December 31, 2017, $1.0 billion of the loans sold had settled while $481 million were classified as held for sale. As of January 17, 2018, 99% of the year-end loans held for sale balance was settled.

The impact of the loan sale and decision to exit the above-mentioned origination operations affected various components of our statement of earnings as follows:

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The following table presents the composition of loans and leases held for investment, net of deferred fees, as of the dates indicated:

(1) Excludes loans held for sale carried at lower of cost or fair value at December 31, 2017 and June 30, 2017.

Included in total loans as of December 31, 2017 were $2.0 billion acquired from CUB, of which $1.3 billion were real estate mortgage loans, $518 million were commercial loans, and $210 million were real estate construction and land loans. In addition, the total unfunded loan commitments as of December 31, 2017 included $914 million associated with loans acquired from CUB.

Deposits and Client Investment Funds

The following table presents the composition of our deposit portfolio as of the dates indicated:

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At December 31, 2017, core deposits totaled $15.9 billion, or 85% of total deposits, including $8.5 billion of noninterest-bearing demand deposits, or 45% of total deposits. Core deposits obtained in the CUB acquisition totaled $2.7 billion.

In addition to deposit products, we also offer alternative non-depository cash investment options for select clients; these alternatives include investments managed by Square 1 Asset Management, Inc. (“S1AM”), our registered investment advisor subsidiary, and third-party sweep products.  Total off-balance sheet client investment funds at December 31, 2017 were $2.1 billion, of which $1.7 billion was managed by S1AM.

PROVISION AND ALLOWANCE FOR CREDIT LOSSES

A provision for credit losses of $6.4 million was recorded in the fourth quarter of 2017 compared to $15.1 million in the third quarter of 2017. The fourth quarter provision consisted of $6.5 million for non-purchased credit impaired (“Non-PCI”) loans and leases and a $0.1 million negative provision for PCI loans; this compares to a third quarter provision of $15.5 million and a $0.4 million negative provision, respectively.  The lower provision for the fourth quarter of 2017 was due mainly to releasing $14.1 million in general reserves relating to the cash flow loan sale. The allowance for Non-PCI credit losses to Non-PCI loans and leases held for investment coverage ratio declined to 0.95% at December 31, 2017 from 1.11% at September 30, 2017. The lower coverage ratio was principally due to the purchase accounting for the CUB acquired loan portfolio, which was not subject to the allowance for credit losses at the time of acquisition.

The following tables show roll forwards of the allowance for credit losses for the periods indicated:

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Gross charge-offs for the fourth quarter of 2017 included $20.1 million for venture capital loans while gross charge-offs for the third quarter of 2017 included $3.4 million for venture capital loans.

Mr. Wagner remarked, “We have taken action to remedy the unacceptably high level of venture capital credit losses during 2017, including adjustments to delegated lending authorities and portfolio management. In addition, significant progress has been made on our initiative to grow the lower-risk capital call line segment of the venture capital loan portfolio.”

The annualized ratio of total net charge-offs to total average loans was 0.52% for the quarter ended December 31, 2017 and 0.43% for the year ended December 31, 2017.

CREDIT QUALITY

Despite the elevated charge-offs on venture capital loans, the Company’s credit quality metrics showed significant improvement during the fourth quarter of 2017.

The following table presents Non-PCI loan and lease credit quality metrics as of the dates indicated:

(1)         Excludes loans held for sale carried at lower of cost or fair value at December 31, 2017.

(2)         Nonaccrual loans include guaranteed amounts of $11.6 million and $9.1 million at December 31, 2017 and September 30, 2017.

(3)         Classified loans include guaranteed amounts of $11.6 million and $9.1 million at December 31, 2017 and September 30, 2017.

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The following table presents Non-PCI nonaccrual loans and leases and accruing loans and leases past due between 30 and 89 days by portfolio segment and class as of the dates indicated:

(1) Excludes loans held for sale carried at lower of cost or fair value at December 31, 2017.

The majority of the loans representing the increase in Non-PCI accruing and 30-89 days past due loans have subsequently been brought current, renewed or are subject to guarantees.

The following table presents nonperforming assets as of the dates indicated:

(1) Excludes loans held for sale carried at lower of cost or fair value at December 31, 2017.

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STOCK REPURCHASE PROGRAM

During the fourth quarter of 2017, the Company amended its existing stock repurchase program to reduce the authorized repurchase amount from $400 million to $150 million and extend the program maturity to December 31, 2018. The Company expects that, subject to market conditions and other factors, the current $150 million share repurchase authorization will be completed during the first quarter of 2018. The Company anticipates an additional repurchase program will be authorized by the Board of Directors in 2018. During the fourth quarter of 2017, we repurchased 2,081,227 shares at an average cost of $47.89 and a total cost of $99.7 million.

ABOUT PACWEST BANCORP

PacWest Bancorp (“PacWest”) is a bank holding company with approximately $25 billion in assets with one wholly-owned banking subsidiary, Pacific Western Bank (the “Bank”). The Bank has 76 full-service branches located throughout the state of California and one branch in Durham, North Carolina. We provide commercial banking services, including real estate, construction, and commercial loans, and comprehensive deposit and treasury management services to small and medium-sized businesses.  We offer additional products and services through our CapitalSource and Square 1 Bank divisions. Our CapitalSource Division provides asset-based, equipment, real estate and security cash flow loans and treasury management services to established middle market businesses on a national basis.  Our Square 1 Bank Division offers a comprehensive suite of financial services focused on entrepreneurial businesses and their venture capital and private equity investors, with offices located in key innovation hubs across the United States.  For more information about PacWest Bancorp, visit www.pacwestbancorp.com, or to learn more about Pacific Western Bank, visit www.pacificwesternbank.com.

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FORWARD LOOKING STATEMENTS

This release contains certain “forward-looking statements” about the Company and its subsidiaries within the meaning of the Private Securities Litigation Reform Act of 1995, including forward-looking statements relating to the Company’s current business plans and expectations regarding future operating results and metrics and including statements about our expectations regarding our future effective tax rate. All statements contained in this release that are not clearly historical in nature are forward-looking, and the words “anticipate,” “assume,” “intend,” “believe,” “forecast,” “expect,” “estimate,” “plan,” “continue,” “will,” “should,” “look forward” and similar expressions are generally intended to identify forward-looking statements. All forward-looking statements (including statements regarding future financial and operating results and future transactions and their results) involve risks, uncertainties and contingencies, many of which are beyond our control, which may cause actual results, performance, or achievements to differ materially from anticipated results, performance or achievements. These risks and uncertainties include, but are not limited to, our ability to compete effectively against other financial institutions in our banking markets; the impact of changes in interest rates or levels of market activity, especially on our loan and investment portfolios; deterioration, weaker than expected improvement, or other changes in the state of the economy or the markets in which we conduct business (including the levels of IPOs and M&A activities); changes in credit quality and the effect of credit quality on our provision for loan and lease losses and allowance for loan and leases losses; our ability to attract deposits and other sources of funding or liquidity; our capital requirements and our ability to generate capital internally or raise capital on favorable terms; the costs and effects of legal, compliance and regulatory actions, changes and developments, including the impact of adverse judgments or settlements in litigation, the initiation and resolution of regulatory or other governmental inquiries or investigations, and/or the results of regulatory examinations or reviews; the Company’s ability to complete future acquisitions and to successfully integrate such acquired entities or achieve expected beneficial synergies and/or operating efficiencies, in each case within expected timeframes or at all; the impact of the Tax Cuts and Jobs Act on our future effective tax rate and our success at managing the risks involved in the foregoing items and all other factors set forth in the Company’s public reports, including the Annual Report on Form 10-K for the year ended December 31, 2016, and particularly the discussion of risk factors within that document.

All forward-looking statements included in this release are based on information available at the time of the release. We are under no obligation to (and expressly disclaim any such obligation to) update or alter our forward-looking statements, whether as a result of new information, future events or otherwise except as required by law.

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PACWEST BANCORP AND SUBSIDIARIES

CONDENSED CONSOLIDATED BALANCE SHEET