Companhia Siderúrgica Nacional S A : 1Q24 - Earnings Release

1Q24 QUARTERLY RESULTS

May 9, 2024

1Q24 RESULTS

São Paulo, May 9, 2024 - Companhia Siderúrgica Nacional ("CSN") (B3: CSNA3) (NYSE: SID) announces its results for the first quarter of 2024 (1Q24) in Reais, with its consolidated financial statements in accordance with the accounting practices adopted in Brazil issued by the Accounting Pronouncements Committee ("CPC"), approved by the Brazilian Securities and Exchange Commission ("CVM") and the Federal Accounting Council ("CFC") and in accordance with the International Financial Reporting Standards ("IFRS") issued by the International Accounting Standards Board ("IASB").

The comments address the Company's consolidated results for the first quarter of 2024 (1Q24) and the comparisons are for the fourth quarter of 2023 (4Q23) and the first quarter of 2023 (1Q23). The dollar exchange rate was R$ 5.08 on 03/31/2023; R$ 4.84 on 12/31/2023 and R$ 4.99 on 03/31/2024.

1Q24 Operational and Financial Highlights

PRICE ADJUSTMENTS IN MINING AND SEASONALITY IN THE DIFFERENT SEGMENTS MARKED THE BEGINNING OF 2024

1Q24 was marked by a strong price adjustment in mining and mix in steel, in addition to a more accentuated seasonality which ended up pressuring the result at the beginning of the year.

As a result, Adjusted EBITDA in 1Q24 reached R$ 2.0 billion, with an EBITDA margin of 19.3%.

THIRD CONSECUTIVE QUARTER OF SALES GROWTH IN THE STEEL INDUSTRY, WITH THE FOREIGN MARKET AS THE COMMERCIAL HIGHLIGHT OF THE PERIOD

Despite the higher sales volume, the prices of steel products remained under pressure and prevented a recovery in the segment. In addition, temporary effects such as higher raw material costs also weighed on the quarter's performance. As a result, the steel industry's adjusted EBITDA was only R$ 234 million in 1Q24, with a margin of 4.3%.

PROFITABILITY OF THE CEMENT SEGMENT EXCEEDS THE 25% MARK FOR THE FIRST TIME SINCE THE INTEGRATION OF LAFARGE HOLCIM'S ASSETS.

The Company continued to make progress in capturing synergies and was able to expand margins even in a quarter marked by weaker seasonality at the beginning of the year.

As a result, the segment's EBITDA margin reached 25.8% in 1Q24, highlighting the positive effects of the price improvement and the strong cost control observed in the period.

RECORD SALES FOR THE PERIOD AND DROP IN IRON ORE PRICES WERE THE HIGHLIGHTS OF THE QUARTER IN MINING

The Company maintained the operational excellence seen in recent quarters to deliver another sales record for the period, surpassing the most critical rainfall period of the year, without major impacts. On the other hand, the sharp drop in the price of iron ore had a significant impact on price realization and, consequently, on the segment's results.

As a result, Adjusted EBITDA from mining reached R$

1.1 billion in 1Q24, with an adjusted EBITDA margin of 39.4%.

LEVERAGE TEMPORARILY PRESSURED BY THE DECLINE IN OPERATING RESULTS

After two consecutive quarters of declining leverage, the indicator rose again due to the weaker results observed in this quarter, which limited cash generation by reflecting the low prices practiced in the period. However, the Company remains firm in its commitment to reduce its level of indebtedness and is advancing in projects that help to recycle the group's capital structure.

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1Q24 RESULTS

Consolidated Table - Highlights

• Adjusted EBITDA is calculated based on net income (loss), plus depreciation and amortization, taxes on profit, net financial result, result from participation in investments, result from other operating revenues/expenses and includes the proportional participation of 37.49% of the EBITDA of the joint subsidiary MRS Logística.
  ² Adjusted EBITDA Margin is calculated from Adjusted EBITDA divided by Managerial Net Revenue.
  ³ Adjusted Net Debt and Adjusted Cash/Availability account for 37.49% of MRS, in addition to not considering Forfaiting and Drawn Risk operations.

Consolidated Income

• Net Revenue totaled R$ 9,713 million in 1Q24, a reduction of 19% when compared to 4Q23, as a result of the combination of the seasonality of the period that leads to lower volumes sold, especially in the mining segment, with lower prices both in the steel industry, but mainly in iron ore, with the strong decline observed in the benchmark index. On the other hand, the logistics segment showed strong dynamism this quarter, overcoming the operational difficulties observed in the same period of 2023 and helping to partially offset the weaker performance of the other segments.
• Cost of Goods Sold (COGS) totaled R$ 7,522 million in 1Q24 and was 10% lower than in the previous quarter, reflecting the weaker commercial activity in the period.
• Gross Profit in 1Q24 fell 40% and was impacted by the weaker operating performance recorded in the period. This effect was also reflected in the Gross Margin, which reached 22.6% and was 8.0 p.p. lower than in the previous quarter.
• General and Administrative Selling Expenses totaled R$ 1,405 million in 1Q24 and were 16% higher than in the previous quarter.
• The group of Other Revenues and Operating Expenses was negative by R$ 296 million in 1Q24, which represents a reduction of 59% compared to 4Q23, explained by the positive effect of iron ore hedging operations, which generated a gain of R$ 6 million in the period compared to a loss of R$ 481 million in 4Q23.
• In 1Q24, the Financial Result was negative by R$ 1,125 million, which represents an increase of 104% compared to 4Q23 as a result of the increase in the cost of debt in dollars, in addition to the lower impact seen on Usiminas shares.

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1Q24 RESULTS

• Equity Result was positive at R$ 93 million in 1Q24, an evolution of 1% compared to the previous quarter, but a growth of more than 323% compared to the same period in 2023, reflecting the better results presented by MRS in 1Q24.

• In the first quarter of the year, CSN recorded a Net Loss of R$ 480 million, reversing the profit observed in the previous quarter, as a result of lower operating results, mainly in mining, in addition to the negative effect of foreign exchange on financial expenses.

Adjusted EBITDA

*The Company discloses its adjusted EBITDA excluding participation in investments and other operating income (expenses) because it understands that they should not be considered in the calculation of recurring operating cash generation.

• Adjusted EBITDA in 1Q24 was R$ 1,966 million, with an Adjusted EBITDA Margin of 19.3% or 9.8 p.p. lower than in the previous quarter. This performance reflects not only the effects of a seasonally weaker period, but mainly the impacts of the strong devaluation in the price of iron ore and the still very difficult competitive environment in the steel segment, with compressed prices and pressure from imported material. On the other hand, it is already possible to see a more positive dynamic for the next results, with an acceleration in demand and a recovery in price, especially in the mining segment.

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1Q24 RESULTS

Adjusted EBITDA (R$ MM) and Adjusted Margin¹ (%)

• The Adjusted EBITDA Margin is calculated by dividing the Adjusted EBITDA and the Adjusted Net Revenue, which considers the 100% participation in the consolidation of CSN Mineração and 37.49% in MRS.

Adjusted Cash Flow

Adjusted Cash Flow in 1Q24 was negative at R$ 636 million, as a result of the combination of weaker operating performance and the negative effect of foreign exchange on financial expenses. This ended up more than offsetting the positive impacts of working capital and lower investments made in the quarter.

Adjusted Cash Flow¹ in 1Q24 (R$ MM)

• The concept of adjusted cash flow is calculated based on Adjusted EBITDA, subtracting EBITDA of the Joint Subsidiaries, CAPEX, Income Tax, Financial Result and changes in Assets and Liabilities², excluding the effect of the Glencore advance.
  ² Adjusted Working Capital is composed of the change in Net Working Capital, plus the change in long-term assets and liabilities accounts and disregarding the net change in income tax and CS.

Indebtedness

On 03/31/2023, consolidated net debt reached R$ 33,431 million, with the leverage ratio measured by the LTM Net Debt/EBITDA ratio reaching 3.13x, which represents a one-off increase of 55 basis points compared to the previous quarter. This increase in the indicator is a direct result of the operational worsening observed in the period, with falling prices and seasonality impacting volumes. However, it is important to note that the outlook is for an improvement in results going forward and that the Company remains firm in its commitment to reduce its debt level and is advancing in projects that help to recycle the group's capital structure. In addition, CSN maintained its policy of carrying a high level of cash, which reached R$ 15 billion in this quarter.

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1Q24 RESULTS

Indebtedness (R$ Billion) and	Net Debt Build-Up
Net Debt / Adjusted EBITDA (x)	(R$ Billions)

¹ Net Debt / EBITDA: To calculate debt, the final dollar of each period is considered, and for net debt and EBITDA, the average dollar of the period.

As mentioned in the 4Q23 Release, on November 30, 2023, the Company concluded the pricing of a new Bond in the amount of US$ 500 million, maturing in 7 years, while on February 8, 2024, it carried out the Retap of this same issuance in the additional amount of US$ 200 million. As a result, a total of US$ 700 million was raised in this last issuance, maturing in 2030.

¹ IFRS: does not consider participation in MRS (37.49%).

• Managerial Gross/Net Debt considers a stake in MRS (37.49%), without accrued interest. ³Average term after completion of the Liability Management Plan.

FX Exposure

The accumulated net foreign exchange exposure in the consolidated balance sheet for 1Q24 was US$ 1,101 million, as shown in the table below, in line with the company's policy of minimizing the impacts of exchange rate volatility on the result.

The Hedge Accounting adopted by CSN correlates the projected flow of exports in dollars with the future maturities of the debt in the same currency. As a result, the exchange variation of the dollar debt is temporarily recorded in the shareholders' equity and is taken to the result when the dollar revenues from such exports occur.

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1Q24 RESULTS

Investments

In terms of Capex, R$ 802 million were invested in 1Q24, 50% less than in 4Q23, but in line with CSN's history of concentrating investments at the end of the year. When compared to the same period in 2023, there is an evolution in the total invested, with emphasis on repairs of the coke batteries, sintering and modernization of operations at UPV, in addition to advances in mining capacity expansion projects, mainly related to new P15 equipment purchases.

Net Working Capital

Net Working Capital applied to the business was negative at R$ 857 million in 1Q24, an increase of 37% when compared to 4Q23, mainly due to the 24% reduction in Accounts Receivable, a figure directly related to sales performance in the period.

The calculation of Net Working Capital applied to the business does not take into account advances on prepayment contracts, as shown in the following table:

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1Q24 RESULTS

¹ Other NWC Assets: Considers employee advances and other accounts receivable.

² Other NWC Liabilities: Considers other accounts payable, dividends payable, installment taxes and other provisions.

• Inventories: Does not consider the effect of the provision for stock/inventory losses. For the calculation of the PME, store stock balances are not taken into account.

Financial Operations

In a continuous objective of extending the amortization period and focusing on long-term operations and in the local capital market, on May 9, 2024, the Company issued its 15th issuance of simple debentures in the total amount of R$ 800 million, with the objective of investing in infrastructure.

Dividends

On May 9, 2024, the Company announced the distribution of interim dividends to its shareholders in the amount of R$ 950 million, which corresponds to R$ 0.72 per share, with payment taking place until May 29, 2024.

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1Q24 RESULTS

Results by Business Segments

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1Q24 RESULTS

Results of the Steel Industry

According to the World Steel Association (WSA), global crude steel production totaled 469.1 million tons (Mt) in the first three months of 2024, up 2.1% from the same period in 2023, reflecting a higher activity in the Middle East and some European countries that helped to offset a weaker dynamic in North America and Southeast Asia. China, which accounted for 54.7% of total global production in 1Q24, recorded a decrease of -2.3 p.p. when compared to the same period in 2023, but a growth of

6.2 p.p. compared to the previous quarter, a movement that reflects the resumption of production and replenishment of inventories at the beginning of the year. Brazilian production, in turn, reached 8.3Mt in the first three months of 2024, which represented an annual growth of 3.8%, highlighted by the operational normalization seen among local producers after a series of shutdowns observed in early 2023. The trend for 2024 is to maintain this strong level of activity, with stronger dynamism among Middle Eastern countries, resumption of activity among European producers and with the Chinese government helping

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