COASTALSOUTH BANCSHARES, INC. REPORTS EARNINGS FOR FOURTH QUARTER 2025

ATLANTA, GA (January 20, 2026) – CoastalSouth Bancshares, Inc. (“CoastalSouth” or the “Company”) (NYSE: COSO), the holding company for Coastal States Bank (the “Bank” or "CSB"), today reported net income of $7.1 million, or $0.58 per diluted share, for the fourth quarter of 2025, compared to approximately $6.7 million, or $0.54 per diluted share, for the third quarter of 2025, and $5.7 million, or $0.54 per diluted share, for the fourth quarter of 2024. For the year ended December 31, 2025, the Company reported net income of $24.9 million, or $2.16 per diluted share, compared with $21.9 million, or $2.09 per diluted share, for the year ended December 31, 2024.

Commenting on the Company’s results, President and Chief Executive Officer, Stephen R. Stone stated, “We are pleased to report record net income for the year of $24.9 million and pre-tax pre-provision net revenue1 ("PPNR") of $34.3 million, which is an increase of 23.6% compared to December 31, 2024. We also produced over $776.0 million in loan commitments and grew core deposits1 by over $120.7 million."

Mr. Stone also announced the Company's strategic expansion into the Charleston, SC market. "This expansion builds upon the strong foundation we have established in the Lowcountry and reflects our continued investment in this dynamic region,” said Stone. "CSB has assembled a locally based commercial banking team with extensive experience serving businesses throughout Charleston and the broader Lowcountry market. The team we have assembled, led by Edward Vaughan, Charleston Market President, will help us continue to drive strong loan and deposit growth."

Fourth Quarter 2025 Performance Highlights:

Operating Highlights

Net interest income totaled $19.9 million for the fourth quarter of 2025, an increase of $673 thousand, or 3.5%, from $19.2 million for the third quarter of 2025 and an increase of $3.6 million, or 22.1% from the fourth quarter of 2024. The Company’s net interest margin expanded to 3.60% for the fourth quarter of 2025, a 2 basis point increase from the third quarter of 2025 and a 39 basis point increase from the fourth quarter of 2024.

The yield on average interest-earning assets for the fourth quarter of 2025 decreased to 5.98% from 6.14% for the third quarter of 2025. This decrease was primarily related to an overall yield decrease in all interest-earning assets, primarily due to the recent interest rate cuts, albeit a significant growth in average total earning assets. Compared to the fourth quarter of 2024, yields on earning assets decreased 4 basis points to 5.98% from 6.02%. The decrease was primarily attributable to the aforementioned interest rate cuts during 2025, offset by significant growth of $171.9 million in average total earning assets, primarily in LHFI.

The Company’s total cost of funds was 2.60% for the fourth quarter of 2025, a decrease of 19 basis points and 39 basis points compared with the third quarter of 2025 and fourth quarter of 2024, respectively. Deposit costs decreased 13 basis points during the fourth quarter of 2025 to 2.59%, compared to 2.72% in the third quarter of 2025. The cost of interest-bearing deposits decreased 14 basis points during the fourth quarter of 2025 to 3.09%, compared with 3.23% in the third quarter of 2025, reflecting continued repricing of certificates of deposits in the fourth quarter of 2025.

Noninterest income totaled $2.3 million for the fourth quarter of 2025, an increase of $195 thousand, or 9.3%, from the third quarter of 2025, primarily attributable to an increase in gain on sale of government guaranteed loans ("GGL"), service charges on deposits, mortgage banking related income and other noninterest income. Noninterest expense totaled $12.3 million for the fourth quarter of 2025, an increase of $406 thousand, or 3.4%, from the third quarter of 2025, primarily due to higher salaries and employee benefits; offset by decreases in other categories, primarily other professional services.

The Company’s effective tax rate for the fourth quarter of 2025 was 18.3%, compared to 23.2% for the third quarter of 2025 and 14.3% for the fourth quarter of 2024. The decrease in effective tax rate from the third quarter of 2025 was primarily due to a higher recognition of benefits from tax credits in the fourth quarter of 2025.

Balance Sheet Trends

Total assets were $2.31 billion at December 31, 2025, an increase of $207.9 million, or 9.9%, from $2.10 billion at December 31, 2024. Loans held for sale ("LHFS") were $170.9 million at December 31, 2025, a decrease of $3.1 million, or 1.8%, from $174.0 million at December 31, 2024. Gross LHFI were $1.62 billion at December 31, 2025, an increase of $207.9 million, or 14.7%, from $1.41 billion at December 31, 2024.

Total deposits were $1.99 billion at December 31, 2025, an increase of $152.9 million, or 8.3%, from $1.83 billion at December 31, 2024. Noninterest-bearing deposits were $312.3 million at December 31, 2025, or 15.7% of total deposits, compared to $302.9 million, or 16.5% of total deposits, at December 31, 2024. Brokered certificates of deposits, a component of time deposits, were $307.0 million at December 31, 2025, as compared to $274.9 million at December 31, 2024, an increase of $32.1 million, or 11.7%.

Credit Quality

During the fourth quarter of 2025, the Company recorded a provision for credit losses of $1.2 million, compared to $653 thousand and $1.2 million during the third quarter of 2025 and fourth quarter of 2024, respectively. The provision expense recorded during the fourth quarter of 2025 was due to increased loan production and other changes in loss rates and economic factors. The Company's annualized net charge-offs (recoveries) to average LHFI ratio was 0.00% for the fourth quarter of 2025 as compared to 0.03% and (0.02)% during the third quarter of 2025 and fourth quarter of 2024, respectively.

Nonperforming assets totaled $18.3 million, or 0.79% of total assets, at December 31, 2025 compared to $15.9 million, or 0.76% of total assets at December 31, 2024. The $2.4 million increase in nonperforming assets at December 31, 2025 from December 31, 2024 was primarily due to the transfer of one senior housing loan to nonaccrual. This is a construction loan for an assisted living facility that is approximately 92% complete and has a current loan-to-value of 55%. Adjusted nonperforming assets3, which excludes the guaranteed portions of nonaccrual loans, was $14.2 million, or 0.62% of total assets, at December 31, 2025 compared to $11.1 million, or 0.53% of total assets, at December 31, 2024.

About CoastalSouth Bancshares, Inc.

CoastalSouth Bancshares, Inc. is a bank holding company headquartered in Atlanta, Georgia. Through our wholly owned subsidiary, Coastal States Bank, a South Carolina state-chartered commercial bank, we offer a full range of banking products and services designed for businesses, real estate professionals, and consumers looking for a deep and meaningful relationship with their bank. To learn more about Coastal States Bank, visit www.coastalstatesbank.com.

Forward-Looking Statements

Statements in this press release regarding future events and our expectations and beliefs about our future financial performance and financial condition, as well as trends in our business and markets, constitute “forward-looking statements” within the meaning of, and subject to the protections of, Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. Forward-looking statements are not historical in nature and may be identified by references to a future period or periods by the use of the words “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 press release should not be relied on because they are based on current information and on assumptions that we make about future events and circumstances that are subject to a number of known and unknown risks and uncertainties that are often difficult to predict and beyond our control. As a result of those risks and uncertainties, and other factors, our actual financial results in the future could differ, possibly materially, from those expressed in or implied by the forward-looking statements contained in this press release and could cause us to make changes to our future plans.

Factors that might cause such differences include, but are not limited to: the impact of current and future economic conditions, particularly those affecting the financial services industry, including the effects of declines in the real estate market, high unemployment rates, inflationary pressures, elevated interest rates and slowdowns in economic growth, as well as the financial stress on borrowers as a result of the foregoing; potential impacts of any adverse developments in the banking industry, including any impacts on customer confidence, deposit outflows, liquidity and the regulatory response thereto; changes in the interest rate environment, including changes to the federal funds rate; changes in prices, values and sales volumes of residential and commercial real estate; competition in our markets that may result in increased funding costs or reduced earning assets yields, thus reducing margins and net interest income; interest rate fluctuations, which could have an adverse effect on the Company’s profitability; a breach in security of our information systems, including the occurrence of a cyber-attack incidents or a deficiencies in cyber security; risks related to potential acquisitions; government actions or inactions, including a prolonged shutdown of the federal government, tariffs, or trade wars (including reduced consumer spending, lower economic growth or recession, reduced demand for U.S. exports, disruptions to supply chains, and decreased demand for other banking products and services), legislation or regulatory changes which could adversely affect the ability of the consolidated Company to conduct business combinations or new operations; changes in tax laws; significant turbulence or a disruption in the capital or financial markets and the effect of a fall in stock market prices on our investment securities; the effects of war or other conflicts, domestic civil unrest and tyranny, and changes in the overall geopolitical landscape; and adverse results from current or future litigation, regulatory examinations or other legal and/or regulatory actions, including as a result of the Company’s participation in and execution of government programs. Therefore, the Company can give no assurance that the results contemplated in the forward-looking statements will be realized.

Additional information regarding these and other risks and uncertainties to which our business and future financial performance are subject is contained in the section titled “Cautionary Note Regarding Forward-Looking Statements” and “Risk Factors” in the Company’s final prospectus filed pursuant to Rule 424(b)(4) under the Securities Act of 1933, as amended, filed with the Securities and Exchange Commission (the “SEC”) on July 2, 2025 (Registration No. 333-287854), relating to our initial public offering, and in other documents that we file with the SEC from time to time, which are available on the SEC’s website, http://www.sec.gov.

In addition, our actual financial results in the future may differ from those currently expected due to additional risks and uncertainties of which we are not currently aware or which we do not currently view as, but in the future may become, material to our business or operating results. 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 press release or to make predictions based solely on historical financial performance.

Any forward-looking statement speaks only as of the date on which it is made, and we do not undertake any obligation to update or review any forward-looking statement, whether as a result of new information, future developments or otherwise, except as required by law. All forward-looking statements, express or implied, included in this press release are qualified in their entirety by this cautionary statement.

(1) Considered non-GAAP financial measure - See "Non-GAAP Financial Measures” and reconciliation of GAAP to non-GAAP financial measures in tables 10A - 10I.

(2) The Company did not have securities held to maturity in any of the periods presented.