The accounting policies have been consistently applied to all consolidated companies. The consolidated financial statements for the years ended December 31, 2025 and 2024 include the following direct and indirect subsidiaries and joint ventures, associates, as well as the exclusive funds, as follows:

The positions presented as of December 31, 2025 and 2024 and the changes refer to the interest held by CSN in these companies:

The reconciliation of the equity method results of joint-ventures and affiliates and the amount presented in the income statement is presented below and derives from the elimination of CSN's transactions with these companies:

·      ELIZABETH CIMENTOS S.A. (“Elizabeth Cimentos”)

On August 31, 2021, the acquisition of control of Elizabeth Cimentos and Elizabeth Mineração was completed through the Group’s subsidiary CSN Cimentos.

Elizabeth Cimentos, which is located in Paraíba, was constituted as a corporation, and maintains operations in the manufacture and sale of portland cement and clinker. Its products are sold in the states comprising Brazil’s North and Northeast regions.

Elizabeth Mineração merged with CSN Cimentos on April 29, 2022.

·      SEPETIBA TECON S.A. (“Tecon”)

Its objective is the exploration of the “Terminal de Contêiners do Porto Organizado de Itaguaí” (Container Terminal of the Organized Port of Itaguaí), located in Itaguaí, in the state of Rio de Janeiro. The terminal is connected to ““UPV - USINA PRESIDENTE VARGAS” (PRESIDENTE VARGAS STEEL MILL) – Usina Presidente Vargas” (Presidente Vargas Steel Mill) via the Southeast railway network, conceded to MRS Logística S.A. Services include container, steel product, and general cargo handling and storage operations, among other services such as container washing, maintenance, and sanitization.

Tecon was the winner of the bidding process and on October 23, 1998 signed the lease for the operation of the port terminal for a period of 25 years, starting in 2001, which can be extended if the granting authority gives a positive statement.

Upon termination of the lease contract, all rights and benefits transferred to Tecon, along with Tecon's property assets and those resulting from investments made in leased assets, will be returned to the Union, declared reversible by the Union as necessary for the continuity of the leased terminal's operation. The assets declared as reversible will be compensated by the Union for the residual value of their cost, determined by Tecon's accounting records after deducting depreciation.

·      ESTANHO DE RONDÔNIA S.A. (“ERSA”)

Headquartered in the state of Rondônia, the subsidiary operates two units, one located in the city of Itapuã do Oeste/RO and the other in Ariquemes/RO. The mining operation is based in Itapuã do Oeste, where cassiterite (tin ore) is extracted, and the smelting is located in Ariquemes, where metallic tin is obtained, which is the raw material used in the “UPV – Usina Presidente Vargas” (Presidente Vargas Steel Mill) for the manufacture of metal sheets.

·      COMPANHIA METALÚRGICA PRADA (“Prada”)

Prada operates in two segments sectors: steel metal packaging and flat steel processing and distribution.

Packaging

In the steel metal packaging segment, Prada produces the best and safest products in cans, buckets and aerosols. It serves the chemical and food segments, providing packaging and lithography services for the main market companies.

Distribution

Prada also operates around processing and distribution of flat steels, with a diversified product line. Provides coils, rolls, sheets, strips, blanks, metal sheets, profiles, tubes and tiles, among other products, for the most different industry segments - from automotive to civil construction. It also specialized in providing steel processing services, meeting the demand of companies throughout the country.

·      METALGRÁFICA IGUAÇU S.A. (“Metalgráfica”)

Founded in 1951, Metalgráfica has units in Ponta Grossa (PR) and Goiânia (GO) and produces steel cans for the national market of metal packaging for food. Its operation is a strategic asset for CSN's packaging division. The technology used by Metalgráfica is more modern than that used by Prada, improving business competitiveness and strengthening the national chain, especially in relation to substitute packaging.

·      CSN ENERGIA S.A. (“Energia”)

Its main objective is the commercialization of electric energy to supply the operational needs of its Parent Company and its respective subsidiaries. If there is a surplus of the purchased energy, it is sold to the market through the Electric Energy Trading Chamber (“CCEE”). The office of the registered company is located in Volta Redonda - Rio de Janeiro.

·      FTL - FERROVIA TRANSNORDESTINA LOGÍSTICA S.A. (“FTL”)

Company created to incorporate the spun-off portion of Transnordestina Logística S.A. It operates public rail freight transport services in Brazil's northeastern network, on sections between the cities of São Luís and Altos, Altos and Fortaleza, Fortaleza and Sousa, Sousa and Recife/Jorge Lins, Recife/Jorge Lins and Salgueiro, Jorge Lins and Propriá, Paula Cavalcante and Cabedelo (Cabedelo Branch) and Itabaiana and Macau (Macau Branch) ("Malha I" – Railway Network number I).

·      CSN MINERAÇÃO S.A. (“CSN Mineração”)

Based in Congonhas, in the state of Minas Gerais, CSN Mineração S.A.'s main objective is the production, purchase and sale of iron ore, and has the foreign market as its focus for marketing its products. On November 30, 2015, CSN Mineração S.A. began centralizing CSN's main iron ore mining operations, including the establishments of the Casa de Pedra mine, the Tecar port, and an 29.90% stake in MRS. CSN's interest in this subsidiary is 69.01% as of December 31, 2025 and 2024.

On November 21, 2023, CSN Mining International GmbH was established as a wholly owned subsidiary of CSN Mining Holding S.L.U., which is itself a wholly owned subsidiary of CSN Mineração. Located in Zug, Canton of Zug, Switzerland, its purpose is to market raw materials of any type and other goods in its own name and on behalf of third parties, both in Switzerland and abroad, and may perform or intermediate services directly or indirectly related to this objective or associated with it.

· MINÉRIOS NACIONAL S.A. (“Minérios Nacional”)

Based in Congonhas, in the state of Minas Gerais, Minérios Nacional's main objective is the production and sale of iron ore. The subsidiary concentrates the mineral rights assets related to the Fernandinho, Cayman and Pedras Pretas mines, all located in Minas Gerais, transferred to Minérios Nacional S.A. in the business combination operation that occurred in 2015.

·      CBSI - COMPANHIA BRASILEIRA DE SERVIÇOS DE INFRAESTRUTURA (“CBSI”)

Based in São Paulo - SP, CBSI's main objective is to provide services to subsidiaries, affiliates, parent company, and other third-party companies, being able to explore activities related to recovery and maintenance of industrial machines and equipment, civil maintenance, industrial cleaning, product logistics preparation, among others.

·      COMPANHIA FLORESTAL DO BRASIL (“CFB”)

Companhia Florestal do Brasil, a legal entity governed by private law, was incorporated on May 24, 2013. It is organized as a privately held corporation and the company's registered office is located in São Paulo.

· STAHLWERK THÜRINGEN GMBH (“SWT”)

SWT was established from the former Maxhütte industrial steel complex, in the city of Unterwellenborn, located in Germany. SWT produces steel profile used for civil construction according to international quality standards. Its main raw material is steel scrap, and its installed production capacity is 1.1 million tons of steel per year. SWT is an indirect subsidiary of CSN Steel S.L.U., a wholly owned subsidiary of CSN.

· COMPANHIA SIDERURGICA NACIONAL – LLC (“CSN LLC”)

Companhia Siderúrgica Nacional, LLC, a wholly owned subsidiary of CSN Steel S.L.U. which, in turn, is a wholly owned subsidiary of CSN, is an importer and marketer of steel products and maintains its activities in the United States.

· LUSOSIDER AÇOS PLANOS, S.A. (“Lusosider”)

Incorporated in 1996, in continuity with Siderurgia Nacional – a company privatized by the Portuguese government that year –, Lusosider is the only Portuguese industry in the steel sector to produce cold-rolled flat steels with anticorrosion coating. The Lusosider has an installed capacity of about 550 thousand tons per year to produce four major groups of steel products: galvanized sheet, cold rolled sheet, pickled sheet and oiled sheet. The products manufactured by Lusosider can be applied in the packaging industry, civil construction (tubes and metallic structures) and in household appliance components.

·      COMPANHIA ESTADUAL DE GERAÇÃO DE ENERGIA ELÉTRICA – CEEE-G.

On October 21, 2022, Companhia Florestal Brasileira (“CFB”) acquired a 66.23% stake in CEEE-G, which previously belonged to the State of Rio Grande do Sul. On December 15, 2022, CFB also subsequently acquired a 32.73% stake in CEEE-G, which was previously part of Centrais Elétricas Brasileiras S.A. – Eletrobras. In November 2023, CEEE-G held an auction for a Public Offer for the Acquisition of Shares ("OPA") to acquire up to 100% of the shares subject to the offer. During the auction, the Company acquired 1,271 common shares and 338 preferred shares, representing 0.017% of its total share capital. The success of the OPA culminated in the conversion of CEEE-G’s registration from a "Category A" to "Category B” company, which was approved by the CVM on January 25, 2024. On February 21, 2024, the company’s held its AGM, which resolved on the compulsory redemption and subsequent cancellation of 98,375 (ninety-eight thousand, three hundred and seventy-five) shares, of which 41,896 (forty-one thousand, eight hundred and ninety-six) and 56,479 (fifty-six thousand, four hundred and seventy-nine) were common and preferred shares issued by CEEE-G, respective, without making changes to the value of its share capital. As a result, as of this date, CFB came to hold 100% of the shares issued by CEEE-G.

Based in Porto Alegre, Rio Grande do Sul State, CEEE-G's main purpose is to conduct studies and implement projects and build and operate electric power plants, as well as to execute business activities resulting from these activities, such as electric energy commercialization. CEEE-G exercises shareholding control over the Special Purpose Entities (SPEs) Ventos de Curupira S.A., Ventos de Povo Novo S.A. and Ventos de Vera Cruz S.A., which were incorporated in February 2014 and members of the consortium responsible for the construction of the Povo Novo Wind Farm Complex.

CEEE-G also holds a 15% participation in the Dona Francisca Consortium, located in Nova Palma, in the state of Rio Grande do Sul, as well as a 30% stake in Companhia Energética Rio das Antas – CERAN, which is located in Florianópolis, in the state of Santa Catarina.

The Company's indirect equity interest in CEEE-G, as of December 31, 2025, is 100%.

·      COMPANHIA ENERGÉTICA CHAPECÓ – CEC

CEC, based in São Paulo, is an independent power producer whose main activity is harnessing electric power potential on the Chapecó River through a hydroelectric plant located between the municipalities of Ipuaçu and São Domingos in the state of Santa Catarina, called Central Geradora Quebra-Queixo. On December 11, 2000, CEC signed a Concession Agreement for the Use of Public Property for the generation of electricity No. 94/2000 with the National Electric Energy Agency – ANEEL. The concession has a term of 35 years counted from the date of contract signature by the granting authority, which may be extended under conditions established by ANEEL, provided that the hydroelectric project exploitation meets the contract conditions and sector legislation.

·      CSN CIMENTOS BRASIL S.A (“CSN Cimentos Brasil”)

Acquired on September 6, 2022, CSN Cimentos Brasil is constituted as a corporation, domiciled in Brazil, with its headquarters located in Santa Cruz, Rio de Janeiro - RJ. This subsidiary of CSN has industrial plants, warehouses and branches in much of the national territory. Its main activities are production, industry and general trade of cement, lime, mortar, minerals and metals in general and complementary products for civil construction, in natura. CSN's equity interest in CSN Cimentos Brasil as of December 31, 2024 is 99.99%.

·      CSN CIMENTOS S.A. (“CSN CIMENTOS”)

The cement segment operations began in the Group in May 2009, through a grinding unit in Volta Redonda/RJ, driven by the synergy between this activity and the slag generation produced by the blast furnaces of “UPV – Usina Presidente Vargas” (Presidente Vargas Stell Mill), a material used as the main raw material for cement production.

In 2011, its own clinker production was started, with the installation of a rotary clinker kiln in Arcos, Minas Gerais, using calcitic limestone extracted from the Bocaina Mine, existing in the same location that also supplies the steel limestone to the “UPV – Usina Presidente Vargas” (Presidente Vargas Steel Mill). This clinker produced is primarily sent by railway to the cement factory in Volta Redonda/RJ.

In 2015, the Arcos/MG unit started cement production with the installation of two vertical cement mills and in 2016 a second clinker production line was installed, thus achieving self-sufficiency of clinker in cement production.

The main product of Arcos is CP-II type cement, basically composed of clinker, slag, limestone, and gypsum, with the composition varying according to the product. Still in Arcos, there is exploration of calcitic limestone and dolomite, which is destined for the “UPV – Usina Presidente Vargas” (Presidente Vargas Steel Mill).

On August 31, 2023, the reverse merger of CSN Cimentos by CSN Cimentos Brasil was approved with the transfer of all assets, property (movable and immovable), rights and obligations. The Appraisal Report of CSN Cimentos' shareholders' equity was prepared based on a specific balance sheet with a base date of June 30, 2023.

As a result of the merger, CSN Cimentos Brasil's shareholders' equity was increased by R$ 2,383,276, of which R$ 2,300,489 were allocated to the share capital and R$ 82,786 to the capital reserve account.

·      CSN ITC Solutions AG (“CSN ITC”)

CSN ITC was incorporated on March 5, 2025. The Company holds a direct take 55.2% in CSN ITC through its indirect subsidiary CSN Mining International GmbH, which holds an 80% stake in CSN ITC. Located in Switzerland, the entity is constituted as a corporation. CSN ITC's activities consist of the sale, distribution, and processing of iron ore and related products in key strategic expansion markets, with the objective of adding value to these products. It has been exploring and seeking out business opportunities in Switzerland and/or other countries.

·      Gramperfil S.A. (“Gramperfil”)

On March 23, 2025, Gramperfil was acquired for the total amount of EUR 11,801 on March 23, 2025. The entirety of its share capital is held by CSN Steel S.L.U., which is located in Portugal and constituted as a corporation. Gramperfil’s business activities consist of producing, selling and processing metal profiles and accessories, in addition to importing and exporting such products for use in metal structures in civil construction.

·      Estrela Comércio e Participações S.A. (“Estrela Group”)

On April 1, 2025, CSN acquired shares representing 70% of Estrela Comércio e Participações S.A.’s ("Estrela”) share capital for the price of R$ 752,494 million reals. Whereas Estrela holds an equity interest in the following companies: Tora Transportes Ltda., Tora Locações S.A., FJX Transportes S.A., N. Minas Transportes e Locações Ltda., Saratoga Transportes Ltda., Lokamig Rent a Car S.A., Seminovos Lokamig Ltda., Tora Logística Armazéns e Terminais Multimodais S.A., Tora Recintos Alfandegários S.A. and Tora Seminovos Comércio de Veículos Ltda.("Grupo Estrela"), these companies became part of the series of companies indirectly controlled by the Company. Grupo Estrela, which is mainly located in Minas Gerais, maintains operations in the field of road transport.

·      CSN Captive Insurance Company LLC (“CSN Captive”)

CSN Captive was incorporated on July 8, 2025, and its share capital was paid in full by the Company on August 29, 2025. CSN Captive is located in the United States in the State of Vermont, in the United States of America, and its corporate purpose is to operate in the insurance market, providing insurance coverage to companies in which the Company holds a participation, as well as to third parties.

·      Galvacolor Jerez S.L.U. (“Galvacolor”)

October 18, 2025, the Company indirectly acquired Galvacolor for the amount of EUR 47 million, the entirety of the share capital of which is held by the subsidiary CSN Steel S.L.U. Located in Spain, Galvacolor is incorporated as a single-member limited liability company, and its corporate purpose involves the production of steel profiles and activities involved in the processing and sale of steel and smelting products.

·      Global Dot Com S.A. (“Global Dot”)

On December 5, 2025, the Company came to indirectly hold 80% of the company’s share capital through the subsidiaries CSN Inova Ventures (2.51%) and CSN Inova Soluções S.A. (77.49%). The acquisition was carried out through the conversion of a loan into shares, as well as the purchase of an additional interest totaling R$ 49.9 million. Located in the municipality of Barueri, in the State of São Paulo, Global Dot was constituted as a corporation and aims to provide information services, particularly fleet management services via integrated software.

Additional sale of shares held by MRS Logística S.A.

This transaction was carried out for the total price of R$3,350,000 previously received by CSN. In the consolidated financial statements, the book value of MRS's investment, amounting to (R$998,922), was derecognized and a gain of R$2,351,078 was initially recorded under other operating revenues (see note 29). However, as the transaction was carried out under common control, such gain was eliminated in consolidation as an unrealized profit at CSN Mineração (see note 10.a). Accordingly, there was no impact on the consolidated results at the transaction date. The transaction resulted in an increase in the ownership interest held by non-controlling shareholders in CSN Mineração.

Share buyback program of subsidiary CSN Mineração

CSN Mineração approved, in Board of Directors Meetings, the Share Buyback Programs, for treasury maintenance and subsequent disposal or cancellation, described below:

CSN Mineração’s Share Repurchase Program, for treasury maintenance and subsequent disposal or cancellation, approved on June 28, 2024 by the Board of Directors, consists of:

• Buyback of up to 100,000,000 shares

• Program term from June 28, 2024 to December 19, 2025

• Acquisition price may not be higher than the quotation on the Stock Exchange

• Buyback operations intermediated by qualified financial institutions.

On October 17, 2024, CSN Mineração approved the cancellation of three company shares held in treasury at a meeting of the Board of Directors. The were no changes in the subsidiary’s share capital as a result of the cancellation of shares. The Company’s share capital was therefore divided into 5,485,338,835 shares.

Program for the sale of shares held by the subsidiary CSN Mineração

The purpose of the Share Sale Program is to dispose of shares currently held in treasury as part of the Company's financial management/ investment process in order to contribute to the liquidity of shares on the market. Approved on November 21, 2025 by the Board of Directors, the Program consists of:

• Sale of up to 53,294,297 shares,

• Program implemented from November 24, 2025 to May 21, 2027,

• Acquisition price: Shares will be sold at B3 S.A. - Brasil, Bolsa, Balcão, at market price.

• Repurchase operations will be intermediated by qualified financial institutions.

Distribution of dividends from subsidiary CSN Mineração:

On May 9, 2024, the Board of Directors of CSN Mineração approved the distribution of interim dividends to the profit reserve account in the amount of R$ 1,025,040, corresponding to R$ 0.186869166032 per share, in anticipation of the minimum mandatory dividend.

At a CSN Mineração Board of Directors meeting held on September 30, 2024, the following distributions were approved: extraordinary interim dividends from profits recorded in the balance sheet as of August 31, 2024, totaling R$ 2,375,000, corresponding to R$ 0.43689118448 per share intermediate dividends from the profit reserve from previous fiscal years, in the amount of R$ 160,000, corresponding to R$ 0.02943266927 per share and payment of interest on equity by CSN Mineração in the amount of R$ 465,000, corresponding to R$ 0.08553869507 per share.

On December 27, 2024, CSN Mineração's Board of Directors approved the payment of interest on equity in the amount of R$ 211,610, corresponding to the value of R$ 0.03895595758 per share.

On May 8, 2025, CSN Mineração’s Board of Directors approved the following items:

1. A total amount of R$1,090,000 allocated to the profit reserve account as interim dividends

2. A total net amount of R$178,201 allocated to the profit reserve account as Interest on Equity

On November 4, 2025, CSN Mineração’s Board of Directors approved the following items:

1. Payment in the amount of R$424,206 to the company’s profit reserve account as interim dividends

2. A total net amount of R$479,000 allocated to the profit reserve account as Interest on Equity

On December 26, 2025, CSN Mineração’s Board of Directors approved the following items:

1. Payment in the amount of R$259,712 to the company’s profit reserve account as interim dividends

2. A total net amount of R$163,998 allocated to the profit reserve account as Interest on Equity

Additionally, within the scope of the proposal to allocate the income for the year, the subsidiary CSN Mineração decided to distribute additional dividends in the amount of R$768,596, which will be submitted at the company’s Annual General Meeting for approval.

Approval, Execution and Sale of Minority Interest in Subsidiary CSN Mineração

The Company, during a Board of Directors meeting held on October 17, 2024, approved a Non-Binding Proposal with Itochu Corporation for the sale of a minority stake of up to 11% in its subsidiary CSN Mineração, at a price per share of R$7.50.

On November 5, 2024, at an additional meeting of the Board of Directors, the Company resolved to approve the execution of the Share Purchase Agreement for the sale of 589,304,801 common shares issued by

CSN Mineração for a unit price of R$7.50 per share, in the amount of R$4,419,786. This amount was paid to CSN in cash by Itochu Corporation on the Share transfer date.

After approval of the transaction by the Administrative Council for Economic Defense – CADE, Itochu Corporation became a signatory to the Shareholders' Agreement of CSN Mineração, amended on November 6, 2024, without changing the rights of the parties to such agreement.

From November 12, 2024, due to this operation, CSN now holds 3,785,474,692 common shares issued by CSN Mineração, reducing its direct stake to 69.01%, while Itochu Corporation now holds 589,304,801 common shares issued by CSN Mineração, reaching a direct stake of 10.74% and an indirect stake of 9.26% through Japão Brasil Minério de Ferro Participações LTDA. Therefore, the shareholding composition of CSN Mineração became:

The balance sheet and income statement balances of the companies whose control is shared are shown below and refer to 100% of the companies’ results:

·      ITÁ ENERGÉTICA S.A. - (“ITASA”)

ITASA is a corporation established in July 1996, whose objective is to operate, under concession, the Itá Hydroelectric Power Plant - UHE Itá ("UHE Itá"), with 1,450 MW of installed capacity, located on the Uruguay River, at the border of Santa Catarina and Rio Grande do Sul states. The Itá HPP concession is shared with ENGIE Brasil Energia S.A., and CSN's stake in ITASA is 48.75%.

·      MRS LOGÍSTICA S.A. (“MRS”)

Located in Rio de Janeiro-RJ, the company aims to explore, through onerous concession, the public cargo railway transportation service in the right-of-way of the Southeast Network, located in the Rio de Janeiro, São Paulo, and Minas Gerais axis, from the defunct Rede Ferroviária Federal S.A. - RFFSA. The original concession term of 30 years counted from December 1, 1996, was extended by the granting authority in July 2022 for an additional 30 years counted from December 1, 2026.

MRS can also explore modal transport services related to rail transport and participate in projects aimed at expanding the granted railway services.

For the provision of services, MRS leased from RFFSA, for the same period of the concession, the assets necessary for the operation and maintenance of rail freight transport activities. At the end of the concession, all leased assets will be transferred to the possession of the railway transport operator designated in that same act.

·      CONSÓRCIO DA USINA HIDRELÉTRICA DE IGARAPAVA

Igarapava Hydroelectric Power Plant is located in Rio Grande, in the city of Conquista - MG, and has an installed capacity of 210 MW, consisting of 5 Bulb-type generating units.

CSN holds 17.92% of the investment in the Consortium whose purpose is the production of electric energy for the own consumption of the consortium members, according to the percentage of participation of each company.

·      CONSÓRCIO DA USINA HIDRELÉTRICA DE ITAÚBA

The Itaúba Hydroelectric Power Plant is located on the Jacuí river, in the municipality of Pinhal Grande, state of Rio Grande do Sul, and is composed of 4 Generating Units, with installed power of 500,400.00 KW.

CSN has a direct participation of 39.03% and indirectly through its subsidiaries of an additional 60.96%, totaling a participation of 99.99%.

·      CONSÓRCIO DA USINA HIDRELÉTRICA DE PASSO REAL

The Passo Real Hydroelectric Power Plant is located on the Jacuí river, in the municipality of Salto do Jacuí, state of Rio Grande do Sul, and is composed of 2 Generating Units, with installed power of 158,000.00 KW.

CSN has a direct participation of 56.40% and indirectly through its subsidiaries of an additional 40.15%, totaling a participation of 96.55%.

Its main objective is to explore and develop public cargo railway transportation services in the northeastern Brazil, comprising the sections from Missão Velha - Salgueiro, Salgueiro - Trindade, Trindade - Eliseu Martins, Salgueiro - Suape Port and Missão Velha - Pecém Port ("Malha II" – Railway Network number II). On December 23, 2022, following extensive negotiations involving ANTT, TCU, and the Ministry of Infrastructure at that time, the first amendment to the Concession Contract was signed. This amendment redefined the scope and completion deadlines for TLSA's railway sections, notably providing for the return of the Salgueiro-Porto de Suape section, resulting in a project with the current 1,206 km of railway network and a completion deadline of December 2029.

Management relies on resources from its shareholders and third parties to complete the project, which it expects to be available based on agreements and recent discussions between the parties involved. The amendment signed in 2024 with “Fundo de Desenvolvimento do Nordeste – FDNE” (Northeast Development Fund) for an operation of R$3.6 billion in convertible debentures has made the resources for completing the project practically fully secured. After evaluating this matter, Management has concluded that the going concern basis of accounting is appropriate in the preparation of the project’s financial statements.

Accounting Policy

Equity Method of Accounting and Consolidation

The equity method of accounting for subsidiaries, joint ventures and associates is applied. Other investments are held at fair value or cost.

Subsidiaries: They are entities in which the Company has significant influence over its financial and operating policies and/or potential exercise or convertible voting rights. Subsidiaries are fully consolidated from the date on which control is transferred to the Company and cease to be consolidated on the date on which control ceases.

Joint-ventures and Joint-operations: are all entities in which the Company has jointly contractually controlled control with one or more parties and can be classified as follows:

Affiliates: Are all entities over which the Company has significant influence but not control, generally through a shareholding of 20% to 50% of the voting rights. Investments in affiliates are initially recognized at cost and subsequently measured using the equity method.

Consortiums: Electricity consortiums are a form of collective electricity purchasing that allows groups of consumers to join to negotiate better supply conditions. In the Group, the Company and its subsidiaries CEEE-G, CSN Mineração, Cimentos Brasil, Elizabeth Cimentos, Minérios Nacional, Prada, Estanho de Rondônia and Metalgráfica Iguaçu participate in the listed consortiums. The profit or loss arising from consortium operations is recognized in the consortium companies according to the participation percentage.

Transactions between Subsidiaries, Affiliates, Joint-Ventures and Joint-operations

Unrealized balances and gains on transactions with subsidiaries, joint-ventures and affiliates are eliminated proportionally to CSN’s interest in the entity in question in the consolidation process. Unrealized losses are eliminated in the same way as unrealized gains, but only to the extent that there is no evidence of impairment. The effects on the results of transactions with joint-ventures are also eliminated, where part of the equity in results of joint-ventures is reclassified to financial expenses, cost of products sold and income tax and social contribution.

The subsidiaries and joint-ventures have the same reporting date and accounting policies as those adopted by the Company.

Foreign Currency Transactions and Balances

The transactions in foreign currencies are translated into the functional currency using the exchange rates in effect at the dates of the transactions or valuations when their values are remeasured. Foreign exchange gains and losses resulting from the settlement of those transactions and from the translation at year-end exchange rates of monetary assets and liabilities denominated in foreign currencies are recognized in the income statement as financial result, except when they are recognized in shareholders' equity as a result of foreign operation characterized as foreign investment. Advances made in foreign currencies are recorded at the exchange rate of the date the entity makes the advance payments or receipts, recognizes (transaction date) as a non-monetary asset or non-monetary liability.

The balance of investment properties is shown below:

The Company Management's estimate of the fair value of investment properties was carried out for December 31, 2025. The fair value of investment property at the consolidated as of December 31, 2025 totaled R$3,818,752 (R$2,431,581 as of December 31, 2024).

The estimated average useful lives for the exercises are as follows (in years):

Accounting Policy

The Company’s investment properties consist of land and buildings maintained to earn rental income and capital appreciation. The measurement method used is the acquisition or construction cost less accumulated depreciation and reduction to its recoverable value, when applicable. The accumulated depreciation of buildings is calculated using the straight-line method based on the estimated useful life of the properties subject to depreciation. Land is not depreciated since it has an indefinite useful life.