NATIONAL STEEL CO

Below, we present the sensitivity analysis for risks related to interest rates. The Company considered two different scenarios to assess the impact of variations in these rates: Scenario 1 predicts a horizon of rising interest rates, and Scenario 2 projects a reduction horizon. To carry out the calculation, the closing rates on March 31, 2026 were considered as references, based on a dispersion model, which considers not only the historical variations in interest rates, but also detailed projections by the management.

This approach allows for a comprehensive and precise assessment of potential economic impacts arising from interest rate fluctuations.

The effects on balances in reals related to assets and liabilities linked to interest rates, considering scenarios 1 and 2, are demonstrated below:

(*) The sensitivity analysis is based on the assumption of maintaining as a probable scenario the market values on March 31, 2026 recorded in the Company's assets and liabilities.

(*) Sensitivity analysis is based on the assumption of maintaining market values as of December 31, 2025 recorded in the Company's assets and liabilities as a probable scenario.

The Company is also exposed to market risks related to the volatility of commodity and input prices. In line with its risk management policy, risk mitigation strategies involving commodities may be used to reduce cash flow volatility. These mitigation strategies may incorporate derivative instruments, predominantly forward, futures, and options transactions.

Below are the price risk protection instruments, as shown in the following topics:

a) Cash flow Hedge Accounting – “Platts” Index

To better reflect the accounting effects of the "Platts" hedge strategy on the result, the subsidiary CSN Mineração opted to formally designate the hedge and, consequently, adopted hedge accounting for the iron ore derivative as a hedge accounting instrument for its highly probable future iron ore sales. As a result, the mark-to-market arising from the "Platts" volatility will be temporarily recorded in equity and will be taken to the income statement when the sales occur according to the contracted evaluation period. This allows the recognition of "Platts" volatility on iron ore sales to be recognized at the same time.

The Company has periodically reviewed market scenarios to assess its exposure to iron ore price risk to ensure adequate coverage of market price fluctuations. This process involves monitoring fluctuations and trends in global prices, in addition to considering economic and geopolitical factors that may impact the value of this commodity.

The table below shows the result of the derivative instrument up to March 31, 2026:

(1) The maturity of the operation occurred on March 31, 2026 and its liquidation in early April 2026.

The movement of the amounts related to cash flow hedge accounting - "Platts" index recorded in shareholders' equity on March 31, 2026 is shown as follows:

The cash flow hedge - "Platts" index was fully effective since the contracting of derivative instruments.

To support the designations, the Company prepared formal documentation indicating how the cash flow hedge accounting designation - "Platts" index aligns with CSN's risk management objectives and strategy, identifying the protection instruments used, the hedge object, the nature of the risk to be protected, and demonstrating the expectation of high effectiveness of the designated relationships. Iron ore derivative instruments ("Platts" index) were designated in amounts equivalent to the portion of future sales, comparing the designated amounts with the expected and approved amounts in the budgets of the Management and Board.

b) Cash flow Hedge Accounting