UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER
PURSUANT TO RULE 13a-16 OR 15d-16 OF
THE SECURITIES EXCHANGE ACT OF 1934

For the month of May 2021

Comission File Number 001-32535

Bancolombia S.A.

(Translation of registrant’s name into English)

Cra. 48 # 26-85
Medellín, Colombia
(Address of principal executive offices)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.

Form 20-F þ                    Form 40-F ¨

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1): ¨

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(2): ¨

Indicate by check mark whether the registrant by furnishing the information contained in this form is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

Yes ¨                    No þ

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

BANCOLOMBIA S.A. (NYSE: CIB; BVC: BCOLOMBIA, PFBCOLOM) REPORTS FINANCIAL RESULTS FOR THE FIRST
QUARTER OF 2021.

May 4, 2021. Medellin, Colombia – Today, BANCOLOMBIA S.A. (“Bancolombia” or “the Bank”) announced its earnings results for the first quarter of 2021¹.

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 December 31, 2020 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 means the Bank together with its affiliates, unless otherwise specified. Representative Market Rate, April 1, 2021 $3.678,62 = US$ 1

BANCOLOMBIA: Summary of consolidated financial quarterly results

(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.

As of March 31, 2021, Bancolombia’s assets totaled COP 257,325 billion, which represents an increase of 0.7% compared to 4Q20 and a decrease of 6.7% compared to 1Q20.

During the quarter, the COP depreciated 7.2% versus the USD and over the past 12 months, it appreciated 9.3%. The average exchange rate for 1Q21 was 3.6% lower than that of 4Q20.

The increase in total assets during the first quarter is largely explained by the growth in the loan book and repos portfolio.

The following table shows the composition of Bancolombia’s loans by type and currency:

In 1Q21, gross loans increased by 3.0% when compared to 4Q20 and decreased by 3.4% when compared to 1Q20. During the last twelve months peso-denominated loans grew 2.1% and the dollar-denominated loans (expressed in USD) decreased by 3.4%.

As of March 31, 2021, the operations in Banco Agricola in El Salvador, Banistmo in Panama and BAM in Guatemala, represented 28% of total gross loans.

Gross loans denominated in currencies other than COP, originated by the operations in Central America, the international operation of Bancolombia Panama, Puerto Rico and the USD denominated loans in Colombia, accounted for 34.2% and increased by 9.0% during 1Q21 (when expressed in COP).

Total reserves (allowances in the balance sheet) for loan losses increased by 2.8% during the quarter and totaled COP 17,087 billion, equivalent to 8.7% of gross loans at the end of the quarter.

For further explanation regarding coverage of the loan portfolio and credit quality trends, (see section 2.4. Asset Quality, Provision Charges and Balance Sheet Strength).

The following table summarizes Bancolombia’s total loan portfolio:

As of March 31, 2021, Bancolombia’s net investment portfolio totaled COP 27,444 billion, decreasing by 7.1% from the end of 4Q20 and increasing by 45.1% from the end of 1Q20.

At the end of 1Q21, the debt securities portfolio had a duration of 19.0 months and a weighted average yield to maturity of 3.6%.

As of 1Q21, Bancolombia’s goodwill and intangibles totaled COP 8,013 billion, increasing by 6.7% compared to 4Q20. This variation is explained by the depreciation of the COP against the USD during the quarter.

As of March 31, 2021, Bancolombia’s liabilities totaled COP 228,119 billion, increasing by 0.3% from the end of 4Q20 and decreasing by 7.4% compared to 1Q20.

Deposits by customers totaled COP 184,543 billion (or 80.9% of liabilities) at the end of 1Q21, increasing by 2.1% when compared to 4Q20 and increasing by 0.2% over the last 12 months. The net loans to deposits ratio was 97.6% at the end of 1Q21 increasing when compared to 96.7% at the end of 4Q20.

Bancolombia’s liquidity position continues to be adequate. During 1Q21 the lower total funding cost reflects the higher share of deposits over the total funding mix.

Shareholders’ equity at the end of 1Q21 was COP 27,618 billion, increasing by 4.0% compared to 4Q20 and by 1.6% when compared to 1Q20.

Bancolombia's consolidated solvency ratio under Basel III was 14.79% in 1Q21, while the basic capital ratio (Tier 1) was 11.19%. These levels are above the minimum regulatory levels required under the new regulation in Colombia, which provides a period of 4 years to comply with a minimum of 11.5% of total solvency and 6.0% of basic capital.

The tangible capital ratio, defined as shareholders’ equity minus goodwill and intangible assets divided by tangible assets, was 7.7% at the end of 1Q21.

The annual decrease in risk-weighted assets is mainly explained by the adoption of the new regulation.

(1) Technical capital is the sum of basic and additional capital, minus deductions (14,609 million for 1Q21).

(2) Operational risk only applies to 4Q20 and 1Q21 after the adoption of Basel III regulation.

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

Net income totaled COP 543 billion in 1Q21, or COP 564.05 per share USD 0.61 per ADR. This profit represents a better result compared to the losses presented in the previous quarter and a growth of 61.5% compared to 1Q20. Bancolombia’s annualized ROE for 1Q21 was 8.0% and 1.8% for the last twelve months.

Net interest income totaled COP 2,825 billion in 1Q21, 26.0% more than the one reported in 4Q20, and 3.0% below the figure of 1Q20.

During 1Q21, the investment, interest rate derivatives and repos portfolio generated COP 273 billion, which is 193.8% higher than the value generated in 1Q20 mainly explained by the derivatives book performance during the quarter. Despite an adverse scenario in the capital markets, investments leveraged by derivatives obtained significant income with low capital consumption.

Net Interest Margin

The annualized net interest margin increased to 5.1% during 1Q21. The annualized net interest margin for investments was 1.7%. The positive result of the first quarter in investments is explained by the execution of strategies on the derivatives portfolio, offsetting the negative results of the public and private debt books, as a result of the devaluation in fixed income globally. The annualized net interest margin of the loan portfolio was 5.7%, increasing when compared to the one reported in 4Q20. This quarterly variation is mainly due to the impact on the valuation of the loan portfolio that was previously under credit reliefs. On an annual basis, the effect of the lower net present value of loans resulting from solutions granted to clients is visible, as well as the impact of the reduction in the reference rates by the Central Bank in Colombia and, the lower income accrued by a greater portion of clients in stage 3 under IFRS 9.

Total funding cost decreased during 1Q21. Saving accounts and checking accounts have increased their share over the total funding mix during the last twelve months. Saving accounts accounted by 35% as of 1Q20, by 1Q21 they represent 41%. Checking accounts represented 14% as of 1Q20 and have increased to 16% as of 1Q21. The annualized average weighted cost of deposits was 1.57% in 1Q21, decreasing by 25 basis points when compared to 4Q20 and by 99 basis points when compared to 1Q20.

During 1Q21, net fees and income from services totaled COP 799 billion, growing by 0.6% compared to 4Q20, and by 0.3% compared to 1Q20.

The better performance in fees during the last quarter confirms a positive trend mainly due to the recovery in transaction levels, despite the seasonality of quarters.

Fees from credit, debit cards and commercial establishments went down by 5.1% compared to 4Q20 and went up by 5.3% compared to 1Q20. Fees from asset management and trust services grew 4.4% compared to 4Q20 and 16.7% compared to 1Q20. Fees from our bancassurance business decreased by 22.3% compared to 4Q20 and by 15.4% with respect to 1Q20.

Total other operating income was COP 344 billion in 1Q21, decreasing by 56.3% compared to 4Q20 and by 0.3% compared to 1Q20. This quarterly variation is largely explained by a higher net foreign exchange as a result of the restatement of assets and liabilities.

Revenues from operating leases totaled COP 207 billion in 1Q21, increasing by 8.9% compared to 4Q20 and increasing by 13.4% compared to those reported in 1Q20. The annual increase is due to higher volumes of operations and delivered assets under leasing.

The principal balance for past due loans (those that are overdue for more than 30 days) totaled COP 9,023 billion at the end of 1Q21 and represented 4.7% of total gross loans, decreasing when compared to 4Q20, when past due loans represented 4.9% of total gross loans. During the quarter, charge-offs totaled COP 1,165 billion.

The coverage, measured by the ratio of allowances for loans losses (principal) to PDLs (overdue 30 days), was 171.7% at the end of 1Q21, increasing compared to 164.9% at the end of 4Q20. The deterioration of the loan portfolio (new past due loans including charge-offs) was COP 1,051 billion.

Provision charges (net of recoveries) totaled COP 1.3 trillion in 1Q21. Provisions during the quarter were mostly explained by the deterioration in customer credit ratings due to COVID-19.

Provisions as a percentage of the average gross loans were 2.6% for 1Q21 and 3.7% for the last 12 months. Bancolombia maintains a strong balance sheet supported by an adequate level of loan loss reserves. Allowances (for the principal) for loan losses totaled COP 15,497 billion, or 8.1% of total loans at the end of 1Q21, decreasing when compared to 4Q20.

The following tables present key metrics related to asset quality:

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

* 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 1Q21, operating expenses totaled COP 1,993 billion, decreasing by 4.1% with respect to 4Q20 and by 7.5% with respect to 1Q20.

Personnel expenses (salaries, bonus plan payments and compensation) totaled COP 824 billion in 1Q21, which represents an increase of 12.4% compared to 4Q20 and decrease of 10.5% compared to 1Q20.

During 1Q21, administrative expenses totaled COP 744 billion, decreasing by 17.4% compared to 4Q20 and by 0.7% as compared to 1Q20.

Depreciation and amortization expenses totaled COP 198 billion in 1Q21, decreasing by 12.1% compared to 4Q20 and decreasing by 4.9% compared to 1Q20.

As of March 31, 2021, Bancolombia had 30,628 employees, owned 952 branches, 6,096 ATMs, 19,815 banking agents and served more than 18 million customers.

Income tax for the quarter was COP 206 billion. In the quarter, all operations presented income tax expense, being Colombia the one with the highest share. Such expense was mainly impacted by untaxed dividends from national subsidiaries in Colombia and by tax benefits from investment in fixed assets.

The following table summarizes the financial statements of our operations in each country.

BANCOLOMBIA S.A. (STAND ALONE) - COLOMBIA

BANISTMO- PANAMA

BANCO AGRÍCOLA- EL SALVADOR

GRUPO AGROMERCANTIL HOLDING – GUATEMALA

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 18 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, Cayman 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.