Columbia Banking System : First Quarter 2024 Earnings Release

EXHIBIT 99.1

COLUMBIA BANKING SYSTEM, INC. REPORTS FIRST QUARTER 2024 RESULTS

$0.59	$0.65	$23.68	$16.03
Earnings per diluted common	Operating earnings per diluted	Book value per common share	Tangible book value per common
share	common share 1	share 1

CEO Commentary

"Our first quarter results reflect early progress on our targeted actions to improve our financial performance and drive shareholder value," said Clint Stein, President and CEO. "Enterprise-wide evaluations and targeted changes resulted in tighter expense control and stabilizing deposit costs in the latter part of the quarter. We will continue to exercise prudent expense management, and we expect to see the positive financial impact of near- term initiatives fully reflected in the fourth quarter's expense run rate. Longer-term initiatives will optimize our performance from a revenue, expense, and profitability standpoint. As an organization, Columbia remains laser-focused on regaining our placement as a top-quartile bank across financial metrics as we strive to drive long-term, consistent, repeatable performance."

-Clint Stein, President and CEO of Columbia Banking System, Inc.

1Q24 HIGHLIGHTS (COMPARED TO 4Q23)

1Q24 KEY FINANCIAL DATA

Net Interest

Income and

NIM

Non-Interest

Income and

Expense

Credit Quality

Capital

Notable Items

• Net interest income decreased by $30 million on a linked-quarter basis due to higher deposit costs relative to the fourth quarter and lower income earned on investment securities given slower prepayment activity.
• Net interest margin was 3.52%, down 26 basis points from the prior quarter given the full-quarter effect of deposit repricing and balance mix shift during the fourth quarter.
• Non-interestincome decreased by $15 million due to the quarterly fluctuation in cumulative non- merger fair value accounting and hedges. Excluding these items, non-interest income increased by $1 million.
• Non-interestexpense decreased by $50 million due to lower discretionary spend and the fourth quarter's larger FDIC special assessment.
• Net charge-offs were 0.47% of average loans and leases (annualized), compared to 0.31% in the prior quarter.
• Provision expense of $17 million compares to $55 million in the prior quarter.
• Non-performingassets to total assets was 0.28%, compared to 0.22% as of December 31, 2023.
• Estimated total risk-based capital ratio of 12.0% and estimated common equity tier 1 risk-based capital ratio of 9.8%.
• Declared a quarterly cash dividend of $0.36 per common share on February 9, 2024, which was paid March 11, 2024.
• Recalibrated the commercial CECL model to be more reflective of the post-merger loan portfolio after a full year operating as a combined organization.
• Incurred $4 million in merger-related expense and $5 million in expense related to an FDIC special assessment.

PERFORMANCE METRICS	1Q24	4Q23	1Q23
Return on average assets	0.96%	0.72%	(0.14)%
Return on average common
equity		10.01%	7.90%	(1.70)%
Return on average tangible
common equity 1	14.82%	12.19%	(2.09)%
Operating return on average
assets	1	1.04%	0.89%	0.74%
Operating return on average
common equity 1	10.89%	9.81%	8.66%
Operating return on average
tangible common equity 1	16.12%	15.14%	10.64%
Net interest margin	3.52%	3.78%	4.08%
Efficiency ratio	60.57%	64.81%	79.71%
Operating efficiency ratio, as
adjusted 1	56.97%	57.31%	52.84%
INCOME STATEMENT	1Q24	4Q23	1Q23
($ in 000s, excl. per share data)
Net interest income	$423,362	$453,623	$374,698
Provision for credit losses	$17,136	$54,909	$105,539
Non-interest income	$50,357	$65,533	$54,735
Non-interest expense	$287,516	$337,176	$342,818
Pre-provision net revenue 1	$186,203	$181,980	$86,615
Operating pre-provision net
revenue 1	$200,684	$212,136	$195,730
Earnings per common share -	$0.59	$0.45	($0.09)
diluted
Operating earnings per common	$0.65	$0.56	$0.46
share - diluted 1
Dividends paid per share	$0.36	$0.36	$0.35
BALANCE SHEET	1Q24	4Q23	1Q23
Total assets	$52.2B	$52.2B	$54.0B
Loans and leases	$37.6B	$37.4B	$37.1B
Total deposits	$41.7B	$41.6B	$41.6B
Book value per common share	$23.68	$23.95	$23.44
Tangible book value per share 1	$16.03	$16.12	$15.12

Investor Contact

Jacquelynne "Jacque" Bohlen, SVP/Investor Relations Director, 503-727-4117, [e-mail]

• "Non-GAAP"financial measure. See GAAP to Non-GAAP Reconciliation for additional information.

Columbia Banking System, Inc. Reports First Quarter 2024 Results

April 25, 2024

Page 2

Organizational Update

Columbia Banking System, Inc. ("Columbia," "we," or "our") conducted an enterprise-wide evaluation of our operations during the first quarter of 2024. The full-scale review resulted in consolidated positions, simplified reporting and organizational structures, and an improved profitability outlook. These changes are expected to be carried out during the second and third quarters of 2024. Please refer to the Q1 2024 Earnings Presentation for additional details.

On February 28, 2023, Columbia completed its merger with Umpqua Holdings Corporation ("UHC"), combining the two premier banks in the Northwest to create one of the largest banks headquartered in the West (the "merger"). Columbia's financial results for any periods ended prior to February 28, 2023 reflect UHC results only on a standalone basis. In addition, Columbia's reported financial results for the first quarter of 2023 reflect UHC financial results only until the closing of the merger after the close of business on February 28, 2023. As a result of these two factors, Columbia's financial results for each of the quarters of 2023 and the year ended December 31, 2023 may not be directly comparable to prior reported periods. Under the reverse acquisition method of accounting, the assets and liabilities of Columbia as of February 28, 2023 ("historical Columbia") were recorded at their respective fair values.

Net Interest Income

Net interest income was $423 million for the first quarter of 2024, down $30 million from the prior quarter. The decline reflects higher deposit costs relative to the fourth quarter and lower income earned on investment securities given slower prepayment activity.

Columbia's net interest margin was 3.52% for the first quarter of 2024, down 26 basis points from 3.78% for the fourth quarter of 2023. The contraction was driven by higher average deposit costs, which increased at an accelerated pace through the fourth quarter and into January before stabilizing in the latter part of the first quarter. The cost of interest-bearing deposits increased 34 basis points on a linked-quarter basis to 2.88% for the first quarter of 2024, which compares to 2.90% for the month of March and 2.89% at March 31, 2024. "During the first quarter, we executed a comprehensive review related to how we evaluate and approve deposit pricing," commented Tory Nixon, President of Umpqua Bank. "This resulted in enhanced pricing visibility, which contributed to stability in interest-bearing core deposit rates."

The cost of interest-bearing liabilities benefited from the movement of $1.4 billion in FHLB Advances to the Federal Reserve's Bank Term Funding Program in January, lowering the cost of these funds by approximately 75 basis points. Columbia's cost of interest- bearing liabilities increased 23 basis points on a linked-quarter basis to 3.25% for the first quarter of 2024, which compares to 3.24% for both the month of March and at March 31, 2024. Please refer to the Q1 2024 Earnings Presentation for additional net interest margin change details and interest rate sensitivity information as well as to our non-GAAP disclosures in this press release for the impact of purchase accounting accretion and amortization on individual line items.

Non-interest Income

Non-interest income was $50 million for the first quarter of 2024, down $15 million from the prior quarter. The decline was driven by quarterly fluctuations in fair value adjustments and mortgage servicing rights ("MSR") hedging activity, which collectively resulted in a net fair value loss of $4 million in the first quarter compared to a net fair value gain of $13 million in the fourth quarter, as detailed in our non-GAAP disclosures. Excluding these items, non-interest income increased by $1 million from the prior quarter.

Non-interest Expense

Non-interest expense was $288 million for the first quarter of 2024, down $50 million from the prior quarter level. Excluding merger- related expense, exit and disposal costs, and accruals for the FDIC special assessment, non-interest expense was $277 million2, down $17 million from the prior quarter due to lower discretionary spending and other expense items compared to elevated expense items in the fourth quarter. Please refer to the Q1 2024 Earnings Presentation for additional expense details.

Balance Sheet

Total consolidated assets were $52.2 billion as of March 31, 2024, unchanged from December 31, 2023. Cash and cash equivalents was $2.2 billion as of March 31, 2024, also unchanged from December 31, 2023. Including secured off-balance sheet lines of credit, total available liquidity was $18.6 billion as of March 31, 2024, representing 36% of total assets, 45% of total deposits, and 138% of uninsured deposits. Available-for-sale securities, which are held on balance sheet at fair value, were $8.6 billion as of March 31, 2024, a decrease of $213 million relative to December 31, 2023 due to paydowns and a decline in the fair value of the portfolio. Please refer to the Q1 2024 Earnings Presentation for additional details related to our securities portfolio and liquidity position.

• "Non-GAAP"financial measure. See GAAP to Non-GAAP Reconciliation for additional information.

Columbia Banking System, Inc. Reports First Quarter 2024 Results

April 25, 2024

Page 3

Gross loans and leases were $37.6 billion as of March 31, 2024, an increase of $200 million relative to December 31, 2023. Commercial line utilization and construction project activity were the primary contributors to the 2% annualized loan growth in the quarter. Higher commercial real estate ("CRE") term balances reflect projects that transitioned from construction to permanent financing. Excluding this shift, origination volume during the first quarter was centered in our commercial and owner-occupied CRE portfolios. Please refer to the Q1 2024 Earnings Presentation for additional details related to our loan portfolio, which include underwriting characteristics, the composition of our commercial portfolios, and disclosure related to our office portfolio.

Total deposits were $41.7 billion as of March 31, 2024, an increase of $99 million relative to December 31, 2023. Customer deposits drove the quarter's increase, enabling a slight reduction in brokered deposits and borrowings. "Our teams are focused on customer deposit generation to reduce wholesale funding sources that create a drag on our earnings power," stated Mr. Nixon. "While inflationary pressures and seasonal patterns affected deposit flows, the teams generated successful momentum through targeted campaigns focused on extraordinary products and service, not price." Please refer to the Q1 2024 Earnings Presentation for additional details related to deposit characteristics and flows.

Credit Quality

The allowance for credit losses was $437 million, or 1.16% of loans and leases, as of March 31, 2024, compared to $464 million, or 1.24% of loans and leases, as of December 31, 2023. The provision for credit losses was $17 million for the first quarter of 2024, and it reflects credit migration trends, changes in the economic forecasts used in credit models, charge-off activity, and a change within our Current Expected Credit Losses ("CECL") methodology. During the first quarter, we recalibrated the commercial CECL model to be more reflective of the post-merger loan portfolio after a full year operating as a combined organization. We believe the recalibrated CECL model is more reflective of the quality of our underwriting and borrower profiles.

Net charge-offs were 0.47% of average loans and leases (annualized) for the first quarter of 2024, compared to 0.31% for the fourth quarter of 2023. Net charge-offs in the FinPac portfolio were $24 million in the first quarter, largely unchanged from the fourth quarter, and were up $14 million in the commercial portfolio from the prior quarter, with the increase centered in a single credit. Charge-off activity in other portfolios, inclusive of a small net recovery in the CRE portfolio, was at an insignificant level. As of March 31, 2024, non-performing assets were $144 million, or 0.28% of total assets, compared to $114 million, or 0.22% of total assets, as of December 31, 2023. The quarter's increase was driven primarily by migration in our SBA portfolio and an owner- occupied CRE property. Nonperforming assets as of March 31, 2024 included $43 million of government guarantees. Please refer to the Q1 2024 Earnings Presentation for additional details related to the allowance for credit losses and other credit trends.

Capital

Columbia's book value per common share was $23.68 as of March 31, 2024, compared to $23.95 as of December 31, 2023. The linked-quarter change primarily reflects a change in accumulated other comprehensive (loss) income ("AOCI") to $(426) million at March 31, 2024, compared to $(340) million at the prior quarter-end. The change in AOCI is due primarily to an increase in the tax- effected net unrealized loss on available-for-sale securities to $413 million as of March 31, 2024, compared to $322 million as of December 31, 2023. Tangible book value per common share3 was $16.03 as of March 31, 2024, compared to $16.12 as of December 31, 2023.

Columbia's estimated total risk-based capital ratio was 12.0% and its estimated common equity tier 1 risk-based capital ratio was

9.8% as of March 31, 2024, compared to 11.9% and 9.6%, respectively, as of December 31, 2023. Columbia remains above current "well-capitalized" regulatory minimums. "Our total risk-based capital ratio at the parent company is now at our long-term target of 12%," stated Ron Farnsworth, Chief Financial Officer of Columbia. "We expect continued organic earnings generation to drive all capital ratios above target levels over time, increasing our flexibility for capital return in the future." The regulatory capital ratios as of March 31, 2024 are estimates, pending completion and filing of Columbia's regulatory reports.

• "Non-GAAP"financial measure. See GAAP to Non-GAAP Reconciliation for additional information.

Columbia Banking System, Inc. Reports First Quarter 2024 Results

April 25, 2024

Page 4

Earnings Presentation and Conference Call Information

Columbia's Q1 2024 Earnings Presentation provides additional disclosure. A copy will be available on our investor relations page: www.columbiabankingsystem.com.

Columbia will host its first quarter 2024 earnings conference call on April 25, 2024, at 2:00 p.m. PT (5:00 p.m. ET). During the call, Columbia's management will provide an update on recent activities and discuss its first quarter 2024 financial results. Participants may register for the call using the below link to receive dial-in details and their own unique PINs or join the audiocast. It is recommended you join 10 minutes prior to the start time.

Register for the call:https://register.vevent.com/register/BI5839ee065d874d2fa744be1fe2d2558d

Join the audiocast:https://edge.media-server.com/mmc/p/jc6j526v/

Access the replay through Columbia's investor relations page: www.columbiabankingsystem.com

About Columbia Banking System, Inc.

Columbia (Nasdaq: COLB) is headquartered in Tacoma, Washington and is the parent company of Umpqua Bank, an award-winning western U.S. regional bank based in Lake Oswego, Oregon. Umpqua Bank is the largest bank headquartered in the Northwest and one of the largest banks headquartered in the West with locations in Arizona, California, Colorado, Idaho, Nevada, Oregon, Utah, and Washington. With over $50 billion of assets, Umpqua Bank combines the resources, sophistication and expertise of a national bank with a commitment to deliver superior, personalized service. The bank supports consumers and businesses through a full suite of services, including retail and commercial banking; Small Business Administration lending; institutional and corporate banking; and equipment leasing. Umpqua Bank customers also have access to comprehensive investment and wealth management expertise as well as healthcare and private banking through Columbia Wealth Advisors and Columbia Trust Company, a division of Umpqua Bank. Learn more at www.columbiabankingsystem.com.

Forward-Looking Statements

This press release includes forward-looking statements within the meaning of the "Safe-Harbor" provisions of the Private Securities Litigation Reform Act of 1995, which management believes are a benefit to shareholders. These statements are necessarily subject to risk and uncertainty and actual results could differ materially due to various risk factors, including those set forth from time to time in our filings with the Securities and Exchange Commission. You should not place undue reliance on forward-looking statements and we undertake no obligation to update any such statements. Forward-looking statements can be identified by words such as "anticipates," "intends," "plans," "seeks," "believes," "estimates," "expects," "target," "projects," "outlook," "forecast," "will," "may," "could," "should," "can" and similar references to future periods. In this press release we make forward-looking statements about strategic and growth initiatives and the result of such activity. Risks and uncertainties that could cause results to differ from forward- looking statements we make include, without limitation: current and future economic and market conditions, including the effects of declines in housing and commercial real estate prices, high unemployment rates, continued inflation and any recession or slowdown in economic growth particularly in the western United States; economic forecast variables that are either materially worse or better than end of quarter projections and deterioration in the economy that could result in increased loan and lease losses, especially those risks associated with concentrations in real estate related loans; our ability to effectively manage problem credits; the impact of bank failures or adverse developments at other banks on general investor sentiment regarding the liquidity and stability of banks; changes in interest rates that could significantly reduce net interest income and negatively affect asset yields and valuations and funding sources; changes in the scope and cost of FDIC insurance and other coverage; our ability to successfully implement efficiency and operational excellence initiatives; our ability to successfully develop and market new products and technology; changes in laws or regulations; any failure to realize the anticipated benefits of the merger when expected or at all; potential adverse reactions or changes to business or employee relationships, including those resulting from the completion of the merger and integration of the companies; the effect of geopolitical instability, including wars, conflicts and terrorist attacks; and natural disasters and other similar unexpected events outside of our control. We also caution that the amount and timing of any future common stock dividends or repurchases will depend on the earnings, cash requirements and financial condition of Columbia, market conditions, capital requirements, applicable law and regulations (including federal securities laws and federal banking regulations), and other factors deemed relevant by Columbia's Board of Directors, and may be subject to regulatory approval or conditions.

Columbia Banking System, Inc. Reports First Quarter 2024 Results

April 25, 2024

Page 5

TABLE INDEX

Consolidated Statements of Operations Consolidated Balance Sheets Financial Highlights

Loan & Lease Portfolio Balances and Mix Deposit Portfolio Balances and Mix Credit Quality - Non-performing Assets Credit Quality - Allowance for Credit Losses

Consolidated Average Balance Sheets, Net Interest Income, and Yields/Rates Residential Mortgage Banking Activity

GAAP to Non-GAAP Reconciliation

Page

6

7

8

9

10

11

12

13

14

15

Columbia Banking System, Inc. Reports First Quarter 2024 Results

April 25, 2024

Page 6

Columbia Banking System, Inc.

Consolidated Statements of Operations

(Unaudited)

					Quarter Ended						% Change
													Year
												Seq.	over
($ in thousands, except per share data)	Mar 31, 2024	Dec 31, 2023	Sep 30, 2023	Jun 30, 2023	Mar 31, 2023		Quarter	Year
Interest income:
Loans and leases	$	575,044	$	577,741	$	569,670	$	552,679	$	413,525		- %	39 %
Interest and dividends on investments:
Taxable		75,017		78,010		80,066		79,036		39,729	(4)%	89 %
Exempt from federal income tax		6,904		6,966		6,929		6,817		3,397	(1)%	103 %
Dividends		3,707		4,862		4,941		2,581		719	(24)%	416 %
Temporary investments and interest bearing deposits		23,553		24,055		34,407		34,616		18,581	(2)%	27 %
Total interest income		684,225		691,634		696,013		675,729		475,951	(1)%	44 %
Interest expense:
Deposits		198,435		170,659		126,974		100,408		63,613	16 %	212 %
Securities sold under agreement to repurchase and
federal funds purchased		1,266		1,226		1,220		1,071		406	3 %	212 %
Borrowings		51,275		56,066		77,080		81,004		28,764	(9)%	78 %
Junior and other subordinated debentures		9,887		10,060		9,864		9,271		8,470	(2)%	17 %
Total interest expense		260,863		238,011		215,138		191,754		101,253	10 %	158 %
Net interest income		423,362		453,623		480,875		483,975		374,698	(7)%	13 %
Provision for credit losses		17,136		54,909		36,737		16,014		105,539	(69)%	(84)%
Non-interest income:
Service charges on deposits		16,064		17,349		17,410		16,454		14,312	(7)%	12 %
Card-based fees		13,183		14,593		15,674		13,435		11,561	(10)%	14 %
Financial services and trust revenue		4,464		3,011		4,651		4,512		1,297	48 %	244 %
Residential mortgage banking revenue (loss), net		4,634		4,212		7,103		(2,342)		7,816	10 %	(41)%
Gain on sale of debt securities, net		12		9		4		-		-	33 %	nm
(Loss) gain on equity securities, net		(1,565)		2,636		(2,055)		(697)		2,416	(159)%	(165)%
Gain on loan and lease sales, net		221		1,161		1,871		442		940	(81)%	(76)%
BOLI income		4,639		4,331		4,440		4,063		2,790	7 %	66 %
Other income (loss)		8,705		18,231		(5,117)		3,811		13,603	(52)%	(36)%
Total non-interest income		50,357		65,533		43,981		39,678		54,735	(23)%	(8)%
Non-interest expense:
Salaries and employee benefits		154,538		157,572		159,041		163,398		136,092	(2)%	14 %
Occupancy and equipment, net		45,291		48,160		43,070		50,550		41,700	(6)%	9 %
Intangible amortization		32,091		33,204		29,879		35,553		12,660	(3)%	153 %
FDIC assessments		14,460		42,510		11,200		11,579		6,113	(66)%	137 %
Merger-related expense		4,478		7,174		18,938		29,649		115,898	(38)%	(96)%
Other expenses		36,658		48,556		42,019		37,830		30,355	(25)%	21 %
Total non-interest expense		287,516		337,176		304,147		328,559		342,818	(15)%	(16)%
Income (loss) before provision (benefit) for income taxes		169,067		127,071		183,972		179,080		(18,924)	33 %	nm
Provision (benefit) for income taxes		44,987		33,540		48,127		45,703		(4,886)	34 %	nm
Net income (loss)	$	124,080	$	93,531	$	135,845	$	133,377	$	(14,038)	33 %	nm
Weighted average basic shares outstanding		208,260		208,083		208,070		207,977		156,383		- %	33 %
Weighted average diluted shares outstanding		208,956		208,739		208,645		208,545		156,383		- %	34 %
Earnings (loss) per common share - basic	$	0.60	$	0.45	$	0.65	$	0.64	$	(0.09)	33 %	nm
Earnings (loss) per common share - diluted	$	0.59	$	0.45	$	0.65	$	0.64	$	(0.09)	31 %	nm

nm = Percentage changes greater than +/-500% are considered not meaningful and are presented as "nm."

Columbia Banking System, Inc. Reports First Quarter 2024 Results

April 25, 2024

Page 7

Columbia Banking System, Inc.

Consolidated Balance Sheets

(Unaudited)

						% Change
							Year
						Seq.	over
($ in thousands, except per share data)	Mar 31, 2024	Dec 31, 2023	Sep 30, 2023	Jun 30, 2023	Mar 31, 2023	Quarter	Year

Assets:
Cash and due from banks	$	440,215	$	498,496	$	492,474	$	538,653	$	555,919	(12)%	(21)%
Interest-bearing cash and temporary
investments		1,760,902		1,664,038		1,911,221		2,868,563		3,079,266	6 %	(43)%
Investment securities:
Equity and other, at fair value		77,203		76,995		73,638		76,361		76,532		- %	1 %
Available for sale, at fair value		8,616,545		8,829,870		8,503,986		8,998,428		9,249,600	(2)%	(7)%
Held to maturity, at amortized cost		2,247		2,300		2,344		2,388		2,432	(2)%	(8)%
Loans held for sale		47,201		30,715		60,313		183,633		49,338	54 %	(4)%
Loans and leases		37,642,413		37,441,951		37,170,598		37,049,299		37,091,280	1 %	1 %
Allowance for credit losses on loans and leases		(414,344)		(440,871)		(416,560)		(404,603)		(417,464)	(6)%	(1)%
Net loans and leases		37,228,069		37,001,080		36,754,038		36,644,696		36,673,816	1 %	2 %
Restricted equity securities		116,274		179,274		168,524		258,524		246,525	(35)%	(53)%
Premises and equipment, net		336,869		338,970		337,855		368,698		375,190	(1)%	(10)%
Operating lease right-of-use assets		113,833		115,811		114,220		119,255		127,296	(2)%	(11)%
Goodwill		1,029,234		1,029,234		1,029,234		1,029,234		1,030,142		- %	- %
Other intangible assets, net		571,588		603,679		636,883		666,762		702,315	(5)%	(19)%
Residential mortgage servicing rights, at fair
value		110,444		109,243		117,640		172,929		178,800	1 %	(38)%
Bank-owned life insurance		682,293		680,948		648,232		643,727		641,922		- %	6 %
Deferred tax asset, net		356,031		347,203		469,841		362,880		351,229	3 %	1 %
Other assets		735,058		665,740		673,372		657,365		653,904	10 %	12 %
Total assets	$	52,224,006	$	52,173,596	$	51,993,815	$	53,592,096	$	53,994,226		- %	(3)%
Liabilities:
Deposits
Non-interest-bearing	$	13,808,554	$	14,256,452	$	15,532,948	$	16,019,408	$	17,215,781	(3)%	(20)%
Interest-bearing		27,897,606		27,350,568		26,091,420		24,815,509		24,370,566	2 %	14 %
Total deposits												- %	- %
	41,706,160		41,607,020		41,624,368		40,834,917		41,586,347
Securities sold under agreements to repurchase		213,573		252,119		258,383		294,914		271,047	(15)%	(21)%
Borrowings		3,900,000		3,950,000		3,985,000		6,250,000		5,950,000	(1)%	(34)%
Junior subordinated debentures, at fair value		309,544		316,440		331,545		312,872		297,721	(2)%	4 %
Junior and other subordinated debentures, at
amortized cost		107,838		107,895		107,952		108,009		108,066		- %	- %
Operating lease liabilities		129,240		130,576		129,845		132,099		140,648	(1)%	(8)%
Other liabilities		900,406		814,512		924,560		831,097		755,674	11 %	19 %
Total liabilities		47,266,761		47,178,562		47,361,653		48,763,908		49,109,503		- %	(4)%
Shareholders' equity:
Common stock		5,802,322		5,802,747		5,798,167		5,792,792		5,788,553		- %	- %
Accumulated deficit		(418,946)		(467,571)		(485,576)		(545,842)		(603,696)	(10)%	(31)%
Accumulated other comprehensive loss		(426,131)		(340,142)		(680,429)		(418,762)		(300,134)	25 %	42 %
Total shareholders' equity		4,957,245		4,995,034		4,632,162		4,828,188		4,884,723	(1)%	1 %
Total liabilities and shareholders' equity	$	52,224,006	$	52,173,596	$	51,993,815	$	53,592,096	$	53,994,226		- %	(3)%
Common shares outstanding at period end		209,370		208,585		208,575		208,514		208,429		- %	- %

Columbia Banking System, Inc. Reports First Quarter 2024 Results

April 25, 2024

Page 8

Columbia Banking System, Inc.

Financial Highlights

(Unaudited)

					Quarter Ended						% Change
		Mar 31,		Dec 31,		Sep 30,		Jun 30,		Mar 31,		Seq.	Year over
		2024		2023		2023		2023		2023		Quarter	Year
Per Common Share Data:
Dividends	$	0.36	$	0.36	$	0.36	$	0.36	$	0.35		- %	3 %
Book value	$	23.68	$	23.95	$	22.21	$	23.16	$	23.44	(1)%	1 %
Tangible book value (1)	$	16.03	$	16.12	$	14.22	$	15.02	$	15.12	(1)%	6 %
Performance Ratios:
Efficiency ratio (2)		60.57 %		64.81 %		57.82 %		62.60 %		79.71 %	(4.24)	(19.14)
Non-interest expense to average assets (1)		2.22 %		2.58 %		2.28 %		2.46 %		3.53 %	(0.36)	(1.31)
Return on average assets ("ROAA")		0.96 %		0.72 %		1.02 %		1.00 %		(0.14)%	0.24	1.10
Pre-provision net revenue ("PPNR") ROAA (1)		1.44 %		1.39 %		1.65 %		1.46 %		0.89 %	0.05	0.55
Return on average common equity		10.01 %		7.90 %		11.07 %		10.84 %		(1.70)%	2.11	11.71
Return on average tangible common equity (1)		14.82 %		12.19 %		16.93 %		16.63 %		(2.09)%	2.63	16.91
Performance Ratios - Operating:(1)
Operating efficiency ratio, as adjusted (1), (2), (5), (6)		56.97 %		57.31 %		51.26 %		54.04 %		52.84 %	(0.34)	4.13
Operating non-interest expense to average assets (1)		2.14 %		2.25 %		2.10 %		2.22 %		2.32 %	(0.11)	(0.18)
Operating ROAA (1), (5)		1.04 %		0.89 %		1.23 %		1.27 %		0.74 %	0.15	0.30
Operating PPNR ROAA (1), (5)		1.55 %		1.62 %		1.94 %		1.82 %		2.01 %	(0.07)	(0.46)
Operating return on average common equity (1), (5)		10.89 %		9.81 %		13.40 %		13.77 %		8.66 %	1.08	2.23
Operating return on average tangible common equity (1), (5)		16.12 %		15.14 %		20.48 %		21.13 %		10.64 %	0.98	5.48
Average Balance Sheet Yields, Rates, & Ratios:
Yield on loans and leases		6.13 %		6.13 %		6.08 %		5.95 %		5.55 %		-	0.58
Yield on earning assets (2)		5.69 %		5.75 %		5.65 %		5.48 %		5.19 %	(0.06)	0.50
Cost of interest bearing deposits		2.88 %		2.54 %		2.01 %		1.64 %		1.32 %	0.34	1.56
Cost of interest bearing liabilities		3.25 %		3.02 %		2.72 %		2.45 %		1.82 %	0.23	1.43
Cost of total deposits		1.92 %		1.63 %		1.23 %		0.99 %		0.80 %	0.29	1.12
Cost of total funding (3)		2.27 %		2.05 %		1.81 %		1.61 %		1.16 %	0.22	1.11
Net interest margin (2)		3.52 %		3.78 %		3.91 %		3.93 %		4.08 %	(0.26)	(0.56)
Average interest bearing cash / Average interest earning assets		3.56 %		3.64 %		5.17 %		5.47 %		4.33 %	(0.08)	(0.77)
Average loans and leases / Average interest earning assets		77.87 %		78.04 %		75.64 %		75.18 %		80.96 %	(0.17)	(3.09)
Average loans and leases / Average total deposits		90.41 %		89.91 %		90.63 %		90.98 %		93.01 %	0.50	(2.60)
Average non-interest bearing deposits / Average total deposits		33.29 %		35.88 %		38.55 %		40.05 %		39.55 %	(2.59)	(6.26)
Average total deposits / Average total funding (3)		90.09 %		90.02 %		86.66 %		85.59 %		91.36 %	0.07	(1.27)
Select Credit & Capital Ratios:
Non-performing loans and leases to total loans and leases		0.38 %		0.30 %		0.28 %		0.22 %		0.20 %	0.08	0.18
Non-performing assets to total assets		0.28 %		0.22 %		0.20 %		0.15 %		0.14 %	0.06	0.14
Allowance for credit losses to loans and leases		1.16 %		1.24 %		1.18 %		1.15 %		1.18 %	(0.08)	(0.02)
Total risk-based capital ratio (4)		12.0 %		11.9 %		11.6 %		11.3 %		10.9 %	0.10	1.10
Common equity tier 1 risk-based capital ratio (4)		9.8 %		9.6 %		9.5 %		9.2 %		8.9 %	0.20	0.90

nm = Percentage changes greater than +/-500% are considered not meaningful and are presented as "nm."

1. See GAAP to Non-GAAP Reconciliation.
2. Tax-exemptinterest has been adjusted to a taxable equivalent basis using a 21% tax rate.
3. Total funding = Total deposits + Total borrowings.
4. Estimated holding company ratios.
5. Non-interestexpense adjustments were revised subsequent to the Company's reporting of its earnings results for the three months ended December 31, 2023. The revision includes adding the FDIC special assessment to the non-interest expense adjustments, which removes the special assessment from the Company's calculation of operating non-interest expense. The Company views the special assessment as an infrequent expense that is outside the control of the Company.
6. The operating efficiency ratio has been adjusted to remove B&O taxes and for a tax-equivalent adjustment to BOLI income. The Company views the adjusted operating efficiency ratio as a better representation of its efficiency ratio when compared to other banks as it normalizes for the tax treatment of the adjusted items. The adjustment re-aligns Columbia's calculation of its operating efficiency ratio with its pre-merger calculation.

Columbia Banking System, Inc. Reports First Quarter 2024 Results

April 25, 2024

Page 9

Columbia Banking System, Inc.

Loan & Lease Portfolio Balances and Mix

(Unaudited)

		Mar 31, 2024		Dec 31, 2023		Sep 30, 2023		Jun 30, 2023		Mar 31, 2023		% Change
													Year
												Seq.	over
($ in thousands)		Amount		Amount		Amount		Amount		Amount		Quarter	Year
Loans and leases:
Commercial real estate:
Non-owner occupied term, net	$	6,557,768	$	6,482,940	$	6,490,638	$	6,434,673	$	6,353,550	1 %	3 %
Owner occupied term, net		5,231,676		5,195,605		5,235,227		5,254,401		5,156,848	1 %	1 %
Multifamily, net		5,828,960		5,704,734		5,684,495		5,622,875		5,590,587	2 %	4 %
Construction & development, net		1,728,652		1,747,302		1,669,918		1,528,924		1,467,561	(1)%	18 %
Residential development, net		284,117		323,899		354,922		388,641		440,667	(12)%	(36)%
Commercial:
Term, net		5,544,450		5,536,765		5,437,915		5,449,787		5,906,774		- %	(6)%
Lines of credit & other, net		2,491,557		2,430,127		2,353,548		2,268,790		2,184,762	3 %	14 %
Leases & equipment finance, net		1,706,759		1,729,512		1,728,991		1,740,037		1,746,267	(1)%	(2)%
Residential:
Mortgage, net		6,128,884		6,157,166		6,121,838		6,272,898		6,187,964		- %	(1)%
Home equity loans & lines, net		1,950,421		1,938,166		1,899,948		1,898,958		1,870,002	1 %	4 %
Consumer & other, net		189,169		195,735		193,158		189,315		186,298	(3)%	2 %
Total loans and leases, net of deferred fees and
costs	$	37,642,413	$	37,441,951	$	37,170,598	$	37,049,299	$	37,091,280	1 %	1 %
Loans and leases mix:
Commercial real estate:
Non-owner occupied term, net		17 %		17 %		17 %		17 %		16 %
Owner occupied term, net		14 %		14 %		14 %		14 %		14 %
Multifamily, net		15 %		15 %		15 %		15 %		15 %
Construction & development, net		5 %		5 %		4 %		4 %		4 %
Residential development, net		1 %		1 %		1 %		1 %		1 %
Commercial:
Term, net		15 %		15 %		15 %		15 %		16 %
Lines of credit & other, net		6 %		6 %		6 %		6 %		6 %
Leases & equipment finance, net		5 %		5 %		5 %		5 %		5 %
Residential:
Mortgage, net		16 %		16 %		17 %		17 %		17 %
Home equity loans & lines, net		5 %		5 %		5 %		5 %		5 %
Consumer & other, net		1 %		1 %		1 %		1 %		1 %
Total		100 %		100 %		100 %		100 %		100 %

Columbia Banking System, Inc. Reports First Quarter 2024 Results

April 25, 2024

Page 10

Columbia Banking System, Inc.

Deposit Portfolio Balances and Mix

(Unaudited)

		Mar 31, 2024		Dec 31, 2023		Sep 30, 2023		Jun 30, 2023		Mar 31, 2023		% Change
												Seq.	Year over
($ in thousands)		Amount		Amount		Amount		Amount		Amount		Quarter	Year
Deposits:
Demand, non-interest bearing	$	13,808,554	$	14,256,452	$	15,532,948	$	16,019,408	$	17,215,781	(3)%	(20)%
Demand, interest bearing		8,095,211		8,044,432		6,898,831		6,300,082		5,900,462	1 %	37 %
Money market		10,822,498		10,324,454		10,349,217		10,115,908		10,681,422	5 %	1 %
Savings		2,640,060		2,754,113		3,018,706		3,171,714		3,469,112	(4)%	(24)%
Time		6,339,837		6,227,569		5,824,666		5,227,805		4,319,570	2 %	47 %
Total	$	41,706,160	$	41,607,020	$	41,624,368	$	40,834,917	$	41,586,347		- %	- %
Total core deposits (1)
$	37,436,569	$	37,423,402	$	37,597,830	$	37,639,368	$	39,155,298		- %	(4)%

Deposit mix:
Demand, non-interest bearing	33 %	34 %	37 %	39 %	41 %
Demand, interest bearing	20 %	19 %	17 %	15 %	14 %
Money market	26 %	25 %	25 %	25 %	26 %
Savings	6 %	7 %	7 %	8 %	9 %
Time	15 %	15 %	14 %	13 %	10 %
Total	100 %	100 %	100 %	100 %	100 %

1. Core deposits are defined as total deposits less time deposits greater than $250,000 and all brokered deposits.