For the month of May 2025

Comission File Number 001-32535

(Translation of registrant’s name into English)

Cra. 48 # 26-85

Medellín, Colombia

(Address of principal executive offices)

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If “Yes” is marked, indicate below the file number assigned to the registrant in connection with Rule 12g3-2(b): 82-__________.

•Net income attributable to shareholders in 1Q25 was COP 1.7 trillion. This value represents an increase of 4.5% compared to the previous quarter. Grupo Bancolombia quarterly annualized return on equity (ROE) was 16.3% for the quarter and 15.6% for the last 12 months.

•Gross loan portfolio stood at COP 279 trillion, increasing 7.7% compared with 1Q24 and decreasing 0.3% compared to the previous quarter, driven by a decline in the consumer loan portfolio, partially offset by slight growth in the commercial and mortgage loan portfolios.

•30-day past due loan ratio was 4.64% and the 90-day past due loan ratio was 3.17%. Total provisions charges for 1Q25 increased 18.3% compared to 4Q24 and were COP 1.1 trillion, representing a quarterly annualized cost of credit of 1.59%. All segments showed a good performance in provision expense.

•Shareholders' equity closed at COP 40.6 trillion as of March 31, 2025, down 6.7% compared to the previous quarter, mainly explained by dividends declared at the shareholders' meeting for the 2024 results. The basic solvency ratio was 11.16% and the total solvency ratio was 12.91% for 1Q25, comfortably meeting the required regulatory levels.

•In reference to its digital strategy, Grupo Bancolombia maintained a positive trend in line with results during the last year. As of March 2025, Bancolombia has 9.0 million active digital customers in the APP Personas (over one quarter), as well as 23.5 million accounts in its financial inclusion platform Nequi.

May 5, 2025. Medellín, Colombia – Today, GRUPO BANCOLOMBIA announced its financial results for the first quarter of 2025.1.

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1 This report corresponds to the interim unaudited consolidated financial information of BANCOLOMBIA S.A. and its subsidiaries (“BANCOLOMBIA” or “The Bank”) which Bancolombia controls, amongst others, by owning directly or indirectly, more than 50% of the voting capital stock. This financial information has been prepared based on financial records generated in accordance with International Financial Reporting Standards – IFRS. BANCOLOMBIA maintains accounting records in Colombian pesos, referred to herein as “Ps.” or “COP”. The financial information for the quarter ended June 30, 2024, is not necessarily indicative of the results for any other future interim period. For more information, please refer to the Bank's filings with the Securities and Exchange Commission, which are available on the Commission's website at www.sec.gov.

BANCOLOMBIA’s first IFRS financial statements will cover the year ending in 2015. CAUTIONARY NOTE REGARDING FORWARD LOOKING STATEMENTS: This release contains statements that may be considered forward-looking statements within the meaning of Section 27A of the U.S. Securities Act of 1933 and Section 21E of the U.S. Securities Exchange Act of 1934. All forward-looking statements, whether made in this release or in future filings or press releases or orally, address matters that involve risks and uncertainties; consequently, there are or will be factors, including, among others, changes in general economic and business conditions, changes in currency exchange rates and interest rates, introduction of competing products by other companies, lack of acceptances of new products or services by our targeted customers, changes in business strategy and various others factors, that could cause actual results to differ materially from those indicated in such statements. We do not intend, and do not assume any obligation, to update these forward-looking statements. Certain monetary amounts, percentages and other figures included in this report have been subject to rounding adjustments. Any reference to BANCOLOMBIA or “The Bank” means Bancolombia S.A: together with its affiliates, unless otherwise specified.

Representative Market Rate, January 1, 2024, $4,191.79 US$ 1

(1)Defined as net interest income divided by monthly average interest-earning assets. (2) Net income divided by monthly average assets. (3) Net income divided by monthly average shareholders’ equity. (4) Defined as ADS price divided by ADS book value. (5) Defined as share price divided by share book value. (6) Share prices on the Colombian Stock Exchange. (7) Defined as market capitalization divided by annualized quarter results. (8) Prices at the end of the respective quarter.

1.BALANCE SHEET

1.1.Assets

As of March 31, 2025, Grupo Bancolombia’s assets amounted COP 364,125 billion, decreasing by 2.2% compared to 4Q24, mainly due to a lower cash position resulting from the appreciation of dollar balances at a lower exchange rate. The total portfolio also fell, driven by the contraction in the consumer loan portfolio.

The Colombian peso appreciated by 4.9% against the dollar during the 1Q25, but depreciated by 9.1% over the last 12 months. The average exchange rate was 2.9% higher in 1Q25 compared to 4Q24 and 6.9% over the last 12 months.

1.2.Loan Portfolio

The following table shows the composition of Bancolombia loans on a consolidated basis by type and currency:

Gross loan portfolio decreased compared with the last quarter mainly due to the appreciation of the Colombian peso against the US dollar. Excluding foreign exchange effects, the portfolio would have expanded by 1.3% compared to 4Q24, reflecting modest growth attributable to our more stringent origination policies.

In 1Q25, the gross loan portfolio declined by 0.3% ( increased by1.3% when excluding FX) compared to 4Q24 and increased by 7% compared to 1Q24. In the last 12 months, the loan portfolio in Colombian pesos grew by 6.3% and the portfolio in dollars by 8.5%.

Operations at Banco Agricola (El Salvador), Banistmo (Panama), and Bam (Guatemala) represented 25.5% of the total gross loan portfolio balance in 1Q25. The loan portfolio denominated in currencies other than the Colombian peso represented 31.9% of the total portfolio and decreased by 6.4% during the quarter.

Allowances for loan losses decreased by 4.0% during the quarter, totaling COP 15,533 billion equivalent to 5.6% of the gross loan portfolio.

Quarterly, Bancolombia S.A.'s gross loan portfolio grew by 2.4%, Banco Agromercantil by 0.7% (measured in USD), Banco Agricola by 1.5% (measured in USD), and Banistmo declined by 0.7% (measured in USD). In Colombia, the mortgage and commercial loan portfolios had incremental volumes, while the consumer portfolio decreased except for payroll-deductible loans. It is worth noting that Nequi experienced robust growth in new originations in personal loans. Banco Agricola demonstrated resilience in the consumer segment with quarterly growth, Following the trend from the previous year, focusing on segments with higher risk-adjusted returns.

For a more detailed explanation regarding coverage and portfolio quality, see section 2.4. Asset quality, provision charges, and balance sheet strength.

The following table summarizes Grupo Bancolombia's total portfolio

1.3.Investment Portfolio

As of March 31, 2025, Grupo Bancolombia’s investment portfolio amounted to COP 36,394 billion, reflecting a decrease of 3.1% compared to 4Q24 and an increase of 28.1% relative to 1Q24. Positions in active liquidity operations decreased due to higher liquidity requirements compared to the previous quarter. At the end of the first quarter of 2025, the investment portfolio in debt securities had an average duration of 16.7 months and a yield to maturity of 10.47%.

1.4.Goodwill and intangibles

At the close of 1Q25, Grupo Bancolombia's intangibles and goodwill totaled COP 9,301 billion, a decrease of 4.8% compared to 4Q24. This variation is mainly due to the appreciation of the peso against the dollar and the restatement of balances from foreign subsidiaries

1.5.Funding

As of March 31, 2025, Grupo Bancolombia's liabilities totaled COP 322,436 billion, decreasing by 1.6% compared to 4Q24 and increasing by 7.7% compared to 1Q24.

Customer deposits totaled COP 276,030 billion (85.6% of liabilities) at the end of 1Q25, showing a decrease of 1.1% compared to 4Q24, mainly explained by the decrease in checking accounts, primarily in the corporate and SME segments, due to the reduction of surplus balances from the previous quarter. The net loan to deposit ratio was 95.3% at the end of 1Q25, an increase compared to the 94.3% recorded in 4Q24, due to the lower quarterly decline rate of the loan portfolio over deposits.

In the funding mix, sight deposits continue to be the main source of funding, representing 53% of the total. While savings accounts fell in absolute terms this quarter, they represented a higher share of total funding, reaching 41% of funds. Meanwhile, time deposits increased their share to 37%, driven by online time deposits from retail clients, maintaining the trend observed last year. The balance of loans with financial institutions decreased, mainly due to the prepayment of foreign currency obligations, highlighting the early cancellation of a syndicated loan at Banistmo.

1.6.Shareholders’ Equity and Regulatory Capital

Shareholders' equity attributable at the end of 1Q25 was COP 40,634 billion, a decrease of 6.7% compared to 4Q24 and an increase of 11.4% compared to 1Q24. In March 2025, the earnings distribution of COP 3.75 trillion was approved, explaining the quarterly reduction in equity.

Grupo Bancolombia's total solvency ratio under Basel III was 12.91% in 1Q25, exceeding the required minimum by 141 basis points. The Tier 1 capital ratio was 11.16%, 266 basis points above the minimum requirement. The decline in solvency levels is mainly due to the earnings distribution. The tangible equity ratio was 8.58% at the end of 1Q25.

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(1)Technical capital is the sum of basic and additional capital, minus deductions ($13,798 MM for 4Q24 and $12,714 MM for 1Q25).

(2)Operational risk applies to 1Q24, 4Q24 and 1Q25 after the adoption of Basel III regulation.

(3)Capital adequacy is technical capital divided by risk-weighted assets.

2.INCOME STATEMENT

Net income attributable to equity holders totaled COP 1,738 billion in 1Q25, or COP 1,822.1 per share (USD $1.74 per ADR), increased by 4.5% compared to 4Q24 mainly due to lower operating expenses. Although provisions increased compared to the previous quarter, they remain below the average of the past three years, which contributed positively to net income. Grupo Bancolombia's annualized ROE was 16.3% in 1Q25 and 15.6% over the last 12 months.

2.1.Net Interest Income

Net interest income was COP 5,064 billion in 1Q25, representing an increase of 0.8% compared to 4Q24. This increase is due to the reduction in interest expenses, attributable to lower costs of deposits, resulting from a decrease in the balance of savings and checking accounts and a reduction in the rate of time deposits during the quarter. Additionally, interest income decreased due to lower interest rates applicable to new originations and the variable-rate loan portfolio.

Furthermore, interest income from debt instruments and the valuation of financial instruments amounted to COP 599 billion, which represents a 20.3% decrease for the quarter. This variation mainly responds to the reduction in liquidity operations.

During the first quarter of 2025, loan portfolio interest income slightly decreased due to moderate growth in the loan portfolio and stable active interest rates. Valuation income from financial instruments also fell compared to the previous quarter, reflecting lower investment returns. In contrast, interest expenses declined due to lower costs on time deposit and passive liquidity operations.

The quarterly annualized loan portfolio margin was 7.00%, increasing by 15 basis points compared to 4Q24 and decreasing by 63 basis points compared to 1Q24. The investment NIM dropped 83 basis points to 2.80%. The consolidated NIM rose by 2 basis points from 6.41% to 6.43%.

Time deposits increased by 1.4% compared to 4Q24, while savings and checking accounts decreased by 0.4% and 6.4%, respectively. The annualized weighted average cost was 4.09% in 1Q25, a reduction of 37 basis points compared to 4Q24.

The Central Bank of Colombia kept the monetary policy rate unchanged during the fourth quarter of 2024.

Net income from commissions and other services in the first quarter of 2025 was COP 1,018 billion, recording a decrease of 6.1% compared to 4Q24 and an increase of 0.5% compared to 1Q24.

On a quarterly basis, Bancassurance revenues experienced the largest decline, in nominal terms, due to lower origination dynamics of the consumer segment. Additionally, there was a reduction in debit and credit card commissions, as well as affiliated establishments’ fees, attributable to lower transaction volume compared to the fourth quarter of 2024.

The decrease in commission expenses this quarter reflects lower transaction volume compared to the previous quarter, driven by seasonal factors as year-end typically involves greater activity.

In 1Q25, other operating income totaled COP 846 billion, a decrease of 6.9% compared to 4Q24. This was primarily due to the appreciation of investment properties by Bancolombia and Fondo Inmobiliario Colombia (FIC). Operating lease income amounted to COP 448 billion, decreasing by 6.0% from the previous quarter, owing to the reduction in vehicle leasing and subleasing operations at Bancolombia and Renting Colombia.

Total dividends and other net income from equity investments in 1Q25 amounted to COP 137 billion. This represents a decrease of 10.4% compared to 4Q24 and an increase of 61.9% compared to 1Q25. The quarterly decline is due to lower dividend income from FCP Fondo Inmobiliario Colombia deriving from the performance of P.A. Viva Malls.

The principal balance for past due loans (those that are overdue for more than 30 days) totaled COP 12,582 billion at the end of 1Q25, representing 4.64% of the total gross portfolio. Meanwhile, 90-day past-due totaled COP 8,609 billion, equivalent to 3.17%. Both

indicators showed a decrease during the quarter, reflecting better performance from new vintages, a strategic focus on lower-risk segments, mainly in the consumer portfolio, and successful debt collection management.

The coverage, measured by the ratio of allowances for loan losses (principal) to past-due loans (30 days overdue), was 111.16% at the end 1Q25, experiencing a decrease compared to 112.39% in 1Q24. Loan deterioration (new past-due loans including write-offs) during 1Q25 was COP 1,153 billion. This lower value compared to the last quarter of 2024 is mainly due to better performance in the segment of individuals and small and medium-sized enterprises.

Provision charges (after recoveries) totaled COP 1,099 billion in the first quarter of 2025, representing an increase of 18.3% compared to the fourth quarter of 2024. Despite a decrease in provision expenses within the individuals, SMEs, and large exposures segments, the sequential variation reflects the lack of a provisions release in the consumer segment, unlike the previous quarter.

Provisions as a percentage of the average gross portfolio, quarterly annualized, was 1.59% for 1Q25 and 1.94% for the last 12 months. Grupo Bancolombia maintains a balanced position supported by an adequate level of past-due loan reserves. Loan loss provisions (for the principal) totaled COP 13,986 billion, or 5.2% of the gross portfolio at the end 1Q25, decreasing compared to 4Q24.

The following tables present key metrics related to asset quality:

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(1)Allowances are reserves for the principal of loans.

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*Mortgage loans that were overdue were calculated for past due loans for 120 days instead of 90 days.

Stage 1. Financial instruments that do not deteriorate since their initial recognition or that have low credit risk at the end of the reporting period. (12-month expected credit losses).

Stage 2. Financial instruments that have significantly increased their risk since their initial recognition. (Lifetime expected credit losses).

Stage 3. Financial instruments that have Objective Evidence of Impairment in the reported period. (Lifetime expected credit losses).

During 1Q25, operating expenses totaled COP 3,502 billion, showing a decrease of 7.7% compared to 4Q24 and an increase of 9.8% compared to 1Q24.

Efficiency was 49.6% in 1Q25 and 49.8% for the last 12 months. Personnel expenses (salaries, employee benefits, and bonuses) amounted to COP 1,530 billion in 1Q25, representing a decrease of 0.2% compared to 4Q24 due to lower bonus expenses, partially offset by the salary increase at the beginning of the year; and an increase of 14.7% compared to 1Q24, mainly explained by the annual salary adjustment.

General expenses totaled COP 1,972 billion in the quarter, decreasing by 12.9% compared to the previous quarter and increasing by 6.3% compared to 1Q24. The quarterly decrease is mainly due to lower expenses on technology fees related to projects, license amortization, and marketing, which are usually lower compared to the last quarter of the year. The annual increase is mainly due to higher costs of technology maintenance and licensing,

As of March 31, 2025, Grupo Bancolombia had 34,182 employees, 852 branches, 6,103 ATMs, 34,563 banking agents, and over 33 million customers.

Grupo Bancolombia's income tax reported an expense of COP 699 billion, with an effective rate of 29%. This is due to the tax benefits in Colombia derived from tax-exempt income from the mortgage loan portfolio for social housing, investments in productive fixed assets, and investments in unconventional renewable energies, as well as tax considerations in Guatemala, El Salvador, and Panama related to tax-exempt income from returns on securities issued by those governments.

3.BREAK DOWN OF OPERATIONS

The following tables summarize the financial statements of our operations in each country.

Bancolombia S.A. loan portfolio grew by 2.4% in 1Q25 compared to the previous quarter and 6.6% over the last 12 months. The most significant growth was in the commercial loan portfolio, especially in the corporate segment. The mortgage loan portfolio increased by 4.7% thanks to the interest rate reduction strategy. However, the consumer loan portfolio decreased due to a decline in personal loan and credit cards, as the pace of originations was offset with maturities given its short-term nature, alongside our reinforced origination standards for consumer lending. The funding structure showed a lower balance due to a reduction in savings and checking accounts, partially offset by an increase in time deposits driven by online time deposits from retail clients.

Bancolombia S.A. net income for 1Q25 was COP 1.8 trillion, an increase of 10.3% compared to 4Q24. Interest income decreased due to treasury operations but was offset by higher loan portfolio income. Interest expenses decreased due to lower rates on time deposits. Provision expenses increased as there were no releases in the consumer segment as in the fourth quarter of 2024. Operating expenses decreased due to seasonality, although labor costs rose due to salary increases. The net interest margin for the quarter was 7.3%, and the quarterly annualized ROE was 16.2%.

Banistmo's loan portfolio closed the quarter with a decrease of 0.7% (measured in USD). The mortgage and consumer loan portfolios declined due to the strengthening of origination policies and lower dynamics in credit card and unsecured investment products. The commercial loan portfolio had stable growth of 0.04%. In funding, there was a reduction of 2.7% due to the decline in time deposits from individuals and institutional clients, as well as sight deposits due to seasonality in the last quarter.

Banistmo recorded a net profit of COP 86.5 billion in 1Q25, increasing by 3,506.5% quarterly. Net interest income decreased due to the decreasing revenue from commercial loans, partially offset by lower interest expenses due to the reduction in time deposit balances. Provisions decreased due to parameters update in the mortgage portfolio, better performance in all the segments, and successful collection strategies. Operating expenses also decreased, although labor expenses increased due to higher bonuses. The net interest margin was 3.1% and the quarterly annualized ROE reached 7.4%.

Banco Agricola's loan portfolio closed the quarter with a 1.5% increase (measured in USD). There was an increase in the consumer loan portfolio, mainly in personal loans and credit cards, while the commercial loan portfolio showed growth driven by originations involving clients within the construction sector. Deposits grew during the quarter, particularly sight accounts, with savings accounts showing the highest growth. Both savings and checking accounts impacted growth in the corporate segment. The growth in time deposits stood out among individuals.

The net result for Banco Agricola in 1Q25 was a profit of COP 153.2 billion, representing an increase of 8.2% compared to 4Q24. This increase was mainly due to higher net interest income generation, driven by growth in treasury income due to a higher volume of United States bonds and, to a lesser extent, higher portfolio interest income. Additionally, there was a reduction in interest expenses associated with a decrease in loans from financial institutions and bonds. Net commissions decreased due to lower transaction volumes compared to the last quarter of the year. Net provisions for the period increased due to the growth of the portfolio in higher-risk segments.Operating expenses decreased as spending normalized following the elevated levels observed in the year-end quarter. Banco Agricola's net interest margin for the first quarter of 2025 was 7.0% and the quarterly annualized ROE was 22.7%.

Bam's loan portfolio closed the first quarter of 2025 with a quarterly growth of 0.7% in USD. This increase was mainly driven by the commercial loan portfolio in the corporate segment. In the consumer segment, although there was an increase in credit cards, the total balance ended with a slight decrease. Meanwhile, the mortgage loan portfolio showed marginal growth of 0.1% at the end of the quarter. Regarding the funding structure, favorable dynamics were observed in savings accounts, especially in the business segment. However, there was a decrease in time deposits and checking account balances.

The net result for Bam in 1Q25 was a profit of COP 20.8 billion. Net interest income decreased compared to the previous quarter due to lower interest generation in the commercial and consumer loan portfolios. This decrease was partially offset by higher income from treasury operations, driven by the appreciation of the investment portfolio, as well as lower interest expenses. Provisions showed a lower expense explained mostly by the business segment. Operating expenses decreased due to the seasonality of the first quarter of the year, which tends to have lower expenses compared to the last quarter. Bam's net interest margin for the first quarter of 2025 was 4.6%, and the quarterly annualized ROE was 3.82%.

4.BANCOLOMBIA Company Description (NYSE: CIB, BVC: BCOLOMBIA Y PFBCOLOM)

GRUPO BANCOLOMBIA is a full-service financial conglomerate incorporated in Colombia that offers a wide range of banking products and services to a diversified individual and corporate customer base of more than 33 million customers. GRUPO BANCOLOMBIA delivers its products and services via its regional network comprised of Colombia’s largest non-government owned banking network, El Salvador’s leading financial conglomerate (Banagricola S.A.), International banking and local (Banistmo S.A.) banking subsidiaries in Panama, Guatemala, and Puerto Rico. Together, BANCOLOMBIA and its subsidiaries provide stock brokerage, investment banking, leasing, factoring, consumer finance, fiduciary and trust services, asset management, among others.

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.