Exhibit 99.1

California BanCorp Announces Completion

of $20 Million Subordinated Note Offering

Oakland, Calif., September 30, 2020 – California BanCorp (the “Company”) (Nasdaq: CALB), the parent company of California Bank of Commerce, today announced the sale and issuance of a 5.00% fixed-to-floating rate subordinated note due 2030 (the “Note”) in the principal amount of $20.0 million to an institutional accredited investor. The Company intends to use the net proceeds from the sale of the Note for general corporate purposes, including, but not limited to, the repayment of $12.0 million of outstanding indebtedness under a term loan.

The Note has a stated maturity of September 30, 2030. Prior to September 30, 2025, the Company may redeem the Note only under certain limited circumstances set forth in the Note. On or after September 30, 2025, the Company may redeem the Note, in whole or in part, at its option, at a redemption price equal to 100% of the principal amount of the Note being redeemed. The Note is not subject to redemption at the option of the holder.

The Note initially bears interest at a fixed annual rate of 5.00%, from and including September 30, 2020 to, but excluding, September 30, 2025. From and including September 30, 2025 to, but excluding the maturity date or early redemption date, the interest rate will reset quarterly at a variable rate equal to the then current three-month Secured Overnight Financing Rate provided by the Federal Reserve Bank of New York (the “SOFR”) plus 488 basis points. As provided in the Note, the interest rate on the Note during the applicable floating rate period may be determined based on a rate other than the three-month term SOFR under certain circumstances.

This press release does not constitute an offer to sell, or the solicitation of an offer to buy, any security and shall not constitute an offer, solicitation or sale in any jurisdiction in which such offering would be unlawful. The Note was offered and sold by the Company in a private placement transaction in reliance on an exemption from the registration requirements of the Securities Act of 1933, as amended (the “Securities Act”), pursuant to Section 4(a)(2) of the Securities Act and Rule 506(b) of Regulation D promulgated thereunder.

Wedbush Securities Inc. acted as sole placement agent and Sheppard, Mullin, Richter & Hampton LLP acted as legal counsel to the Company.

About California BanCorp

California BanCorp, the parent company for California Bank of Commerce, offers a broad range of commercial banking services to closely held businesses and professionals located throughout Northern California. The Company’s common stock trades on the Nasdaq Global Select marketplace under the symbol CALB. For more information on California BanCorp, call us at (510) 457-3751, or visit us at www.californiabankofcommerce.com.

Forward-Looking Information

Statements in this news release regarding expectations and beliefs about future financial performance and financial condition, as well as trends in the Company’s business and markets are “forward-looking statements” as defined in the Private Securities Litigation Reform Act of 1995. Forward-looking statements often include words such as “believe,” “expect,” “anticipate,” “intend,” “plan,” “estimate,” “project,” “outlook,” or words of similar meaning, or future or conditional verbs such as “will,” “would,” “should,” “could,” or “may.” The forward-looking statements in this news release are based on current information and on assumptions that the Company makes about future events and circumstances that are subject to a number of risks and uncertainties that are often difficult to predict and beyond the Company’s control. As a result of those risks and uncertainties, the Company’s actual financial results in the future could differ, possibly materially, from those expressed in or implied by the forward-looking statements contained in this news release and could cause the Company to make changes to future plans. Those risks and uncertainties include, but are not limited to, the risk of incurring loan losses, which is an inherent risk of the banking business; the risk that the Company will not be able to continue its internal growth rate; the risk that the United States economy will experience slowed growth or recession or will be adversely affected by domestic or international economic conditions and risks associated with the Federal Reserve Board taking actions with respect to interest rates, any of which could adversely affect, among other things, the values of real estate collateral supporting many of the Company’s loans, interest income and interest

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rate margins and, therefore, the Company’s future operating results; risks associated with changes in income tax laws and regulations; and risks associated with seeking new client relationships and maintaining existing client relationships. Readers of this news release are encouraged to review the additional information regarding these and other risks and uncertainties to which our business is subject that are contained in our Annual Report on Form 10-K for the year ended December 31, 2019 and in our Quarterly Reports on Form 10-Q for the quarters ended March 31, 2020 and June 30, 2020, each of which is on file with the Securities and Exchange Commission.

The COVID-19 pandemic has created economic and financial disruptions that have adversely affected, and may continue to adversely affect, our business, operations, financial performance and prospects. Even after the COVID-19 pandemic subsides, it is possible that the U.S. and other major economies experience or continue to experience a prolonged recession, which could materially and adversely affect our business, operations, financial performance and prospects. Statements about the effects of the COVID-19 pandemic on our business, operations, financial performance and prospects may constitute forward-looking statements and are subject to the risk that the actual impacts may differ, possibly materially, from what is reflected in those forward-looking statements due to factors and future developments that are uncertain, unpredictable and in many cases beyond our control, including the scope and duration of the pandemic, actions taken by governmental authorities in response to the pandemic, and the direct and indirect impact of the pandemic on our customers, third parties and us.

Due to these and other possible uncertainties and risks, readers are cautioned not to place undue reliance on the forward-looking statements contained in this news release, which speak only as of today’s date, or to make predictions based solely on historical financial performance. The Company disclaims any obligation to update forward-looking statements contained in this news release, whether as a result of new information, future events or otherwise, except as may be required by.

California BanCorp

Steven E. Shelton, (510) 457-3751

President and Chief Executive Officer

seshelton@bankcbc.com

Thomas A. Sa, (510) 457-3775

Senior Executive Vice President

Chief Financial Officer and

Chief Operating Officer

tsa@bankcbc.com

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