Ms. Ana Cabral reports

SIGMA LITHIUM EXTENDS 4-YEAR US$100 MILLION SENIOR SECURED DEBT TO JUNE 2027; 7,090T PRODUCED SINCE RESTART

Sigma Lithium Corp. and subsidiary Sigma Mineracao S.A. have signed an agreement letter to extend the maturity of its $100-million (U.S.) in outstanding senior secured debt with Synergy Capital by six months, from December, 2026, to June, 2027. The interest rate on the senior secured facility remained unchanged at SOFR (secured overnight financing rate) plus 6.95 per cent per annum.

Highlights

• Sigma Lithium extends the maturity of its four-year $100-million (U.S.) senior secured debt with Synergy Capital by six months, from December, 2026, to June, 2027.
  • The interest rate on the senior secured facility remained unchanged at SOFR plus 6.95 per cent per annum, as did the covenants and events of default.
• The extension defers Sigma Lithium's repayment by six months, enabling the company to continue ramping up production and building operational cash flow before the new debt maturity date in June, 2027.
• Since operations restarted on Oct. 5, 2026, the company has produced 7,090 tonnes of lithium oxide concentrate up to Oct. 22, 2026.
• Sigma Lithium maintains its target to scale its annualized production of lithium oxide concentrate to 330,000 tonnes by year-end 2027.
• The extension follows a reduction in total debt over the past two years:
  • Repaid more than $90-million (U.S.) in debt since Q2 2024 through cash generation.
  • Reduced total debt by approximately 40 per cent over the past two years, to $125-million (U.S.) as of Oct. 21, 2026.

The extension defers the company's debt final repayment requirement in December, 2026, as a result enabling Sigma Lithium to lengthen 93 per cent of its debt profile to June, 2027, enhancing its financial flexibility, supporting its execution plans.

The extension gives the company time to ramp up production following the restart of operations:

• The company recommenced operations on Oct. 5, 2026, after the Federal Superior Court granted a decision reinstating all its environmental licences.
• The company produced 7,090 t of lithium oxide concentrate between Oct. 5 and Oct. 21, 2026.

Sigma Lithium maintains its target to scale its annualized production of lithium oxide concentrate to 330,000 tonnes by year-end 2027, supported by the company's existing industrial capacity at its Cleantech industrial plant and its recycling and reprocessing circuits (Cleantech industrial plant).

Sigma Lithium will report Q3 2026 production, sales, realized prices, costs and cash by Nov. 13, 2026.

The extension follows a reduction in total debt over the past two years:

• Repaid more than $90-million (U.S.) in debt since Q2 2024 through cash generation;
• Reduced total debt by approximately 40-per-cent over the past two years, to $125-million (U.S.) as of Oct. 21, 2026.

The Extension agreement maintains similar covenants and events of default as the original senior secured debt agreement dated December, 2022.

Ana Cabral, chief executive officer and co-chairperson of Sigma Lithium, stated: "We appreciate the constructive engagement and continued support of Synergy Capital extending our maturity profile ahead of schedule. The six-month extension provides additional time to continue ramping up production ahead of the new maturity date. We have produced more than 6,400 tonnes of high-grade lithium oxide concentrate in the two weeks since operations resumed as we continue to ramp up production."

Ms. Cabral added: "Over the past two years, we have repaid more than $90-million (U.S.) in debt. Together with our low costs and current lithium pricing levels, we expect to regain operational cash flow momentum. Thanks to the hard work of our teams and the trust of our stakeholders, our capital structure enhances our resilience and flexibility as we work toward our 2027 targets."

Sigma Lithium is an economic engine in the Jequitinhonha Valley, one of Brazil's most disadvantaged regions.

Sigma Lithium supports 19,000 jobs and approximately 80,000 family members. The company's economic impact can be seen in the triple-digit GDP (gross domestic product) growth of towns in the Vale do Jequitinhonha (Lithium Valley), where it operates across 12 municipalities:

• Aracuai's GDP per capita grew by 123 per cent and Itinga's by 110 per cent, during the same period.
• Aracuai had the highest GDP per capita in the region, surpassing even larger municipalities such as Teofilo Otoni, which has a population four times larger.
• Economic growth is further demonstrated by the opening of 9,410 new companies between January, 2023, and March, 2026.
• Details of Sigma Lithium's social programs in the Vale do Jequitinhonha, including Dona de Mim, Zero Drought, Water for All and Education that Transforms, are available at the company's website.

Sigma Lithium has generated shared prosperity in the Vale do Jequitinhonha

The scale of Sigma Lithium's social initiatives reflects their impact in the Vale do Jequitinhonha. These initiatives began before the company commenced operations.

The company has supported voluntary programs promoting economic inclusion, access to water, food security, education and drought resilience since before it began generating revenue:

• Dona de Mim: More than 2,000 women have become entrepreneurs through Sigma Lithium's microcredit opportunities, supporting approximately 10,000 family members.
• Zero drought: A total of 1,400 rainwater collection and irrigation structures (Barraginhas) were built to strengthen drought resilience for approximately 5,600 small-scale subsistence farmers.
  • These initiatives support approximately 22,400 rural family members.
• Water for all: Enabled access to drinking water for 100 per cent of Sigma Lithium's neighbouring community.
• Education that transforms: Sigma Lithium renovated and helped build local schools, sports facilities, and a childcare centre, including a state-of-the-art SESI STEM school.
  • These initiatives support educational and extracurricular programs for approximately 776 children, expanding future opportunities for them and approximately 1,500 parents.

The qualified person (QP) for the technical information contained here is Alexandre Rodrigues Cabral, PEng, member of the Ordre des Ingenieurs du Quebec (OIQ, membership No. 105796), who is considered, by virtue of his education, experience and professional association, a qualified person under the terms of National Instrument 43-101. Mr. Cabral is not considered an independent QP under NI 43-101 as he is a Sigma Lithium director and chair of the company's technical committee. Mr. Cabral has reviewed and approved the technical and scientific content of this release.

About Sigma Lithium Corp.

Sigma Lithium is the largest industrial-mineral producer of lithium oxide concentrate in the Americas and is dedicated to industrializing socially and environmentally sustainable lithium materials to supply global producers of batteries for energy security. The company runs one of the world's largest lithium production sites -- the fifth-largest industrial mineral complex for lithium oxide concentrate -- at its Grota do Cirilo operation in Brazil. Sigma Lithium currently has a nameplate capacity to industrialize 330,000 tonnes of lithium oxide concentrate on an annualized basis at its mine and state-of-the-art Cleantech industrial plant.

Sigma Lithium is at the forefront of environmental and social sustainability in the battery materials supply chain. Its Cleantech industrial plant combines nearly 100-per-cent water reuse, zero use of toxic chemicals, no tailings mud dams and 100-per-cent renewable electricity. For more than three years, Sigma Lithium has recorded no lost-time accidents.

The company plans to resume its phase 2 expansion in 2027, which is designed to nearly double annual production capacity to 580,000 tonnes. It also plans a phase 3 expansion to increase capacity further to 830,000 tonnes.

We seek Safe Harbor.