FRONTIER LITHIUM INITIATES MINE AND MILL FEASIBILITY STUDY UPDATE FOR THE PAK LITHIUM PROJECT

SUDBURY, ON, Sept. 10, 2026 /CNW/ -- Frontier Lithium Inc. (TSXV: FL) (OTCQB: LITOF) (FRA: HL2) ("Frontier" or the "Company") is pleased to announce the award of an updated feasibility study for the mine and mill stage of its PAK Lithium Project (the "Project") in northwestern Ontario to DRA Americas Inc.

The feasibility study update will incorporate work completed since the Company's 2025 Feasibility Study ("FS") including the integration of value engineering results achieved to date, and focus on opportunities to optimize project economics, and further de-risk execution planning and development sequencing. Targeted for completion in the first quarter of 2027, the updated feasibility study is a key milestone in advancing the PAK Lithium Project toward financing and construction readiness.

The updated feasibility study is expected to assess refinements to process design, mass and water balance modelling, geotechnical investigations, operating assumptions and throughput scenarios. It will also incorporate the results of ongoing engineering, permitting and infrastructure planning activities, providing an updated development plan and project economics for stakeholders and potential financing partners.

In parallel, Frontier continues to advance permitting and consultation activities under Ontario's One Project, One Process framework (1P1P), together with Indigenous community engagement, environmental studies and infrastructure initiatives that support the future development of the Project. Together with permitting progress, infrastructure planning and strategic partnership initiatives, this work is intended to move the Mine and Mill stage of the Project toward a financing-ready and construction-ready state, while strengthening our path toward a future final investment decision.

"Since completing our 2025 Feasibility Study, we have continued to build meaningful momentum across the PAK Lithium Project through technical advancement, permitting progress, infrastructure planning and strategic partnership initiatives," said Trevor Walker, President and Chief Executive Officer of Frontier Lithium. "This updated feasibility study is about capturing that progress and positioning the Mine and Mill stage for the next phase of development. With one of North America's highest-grade known lithium resources, a strategic location in Ontario and growing demand for secure domestic critical mineral supply, we believe PAK is a standout development opportunity."

On behalf of the Board of Directors

Trevor Walker

Chief Executive Officer and President

Qualified Person Statement

All scientific and technical information in this release has been reviewed and approved by Mr. Garth Drever, P.Geo., VP of Exploration and an employee of the Company, who is not independent of the Company but is a Qualified Person as defined by National Instrument 43-101 – Standards of Disclosure for Mineral Projects.

About Frontier Lithium

Frontier Lithium Inc. is a pre-production mining company with an objective to become a strategic and integrated supplier of premium spodumene concentrates as well as battery-grade lithium salts to the growing electric vehicle and energy storage markets in North America. The Company's PAK Lithium Project maintains the largest land position and resource in a premium lithium mineral district located in Ontario's Great Lakes region.

About the PAK Lithium Project

The PAK Lithium Project is a fully integrated critical minerals initiative in Ontario, developing North America's highest-grade known lithium resource. Operated as a joint venture between Frontier Lithium (92.5%) and Mitsubishi Corporation (7.5%), the Project is advancing in parallel with a mine and mill and a downstream conversion facility in Thunder Bay, Ontario, both key to supporting a secure domestic lithium supply for the clean energy transition. A 2025 Mine and Mill Feasibility Study (FS), prepared by DRA Americas Inc. and entitled National Instrument 43-101 Technical Report FS PAK Lithium Project, Mine and Mill, outlines a 31-year Project life with an after-tax net present value of C$932 million at an 8% discount rate and an after-tax internal rate of return of 17.9%. These results were disclosed in a press release dated May 28, 2025, and the accompanying technical report was filed on July 9, 2025 on SEDAR+ (www.sedarplus.ca).

Cautionary Note Regarding Forward-Looking Statements

This news release includes certain statements that may be deemed "forward-looking statements". All statements in this release, other than statements of historical fact constitute forward-looking statements. Forward-looking statements contained in this news release may include, but are not limited to, statements with respect to: capital requirements and private and/or public financing initiatives, estimated mineral resources, estimated capital costs to construct mine facilities, estimated operating costs, the duration of payback periods, estimated amounts of future production, estimated cash flows, net present value, the FS and an updated feasibility study and statements that address future production, resource and reserve potential, exploration drilling, exploitation activities and events or developments that the Company expects, including but not limited to capital and operating costs, timelines, internal rates of return, and project development milestones.

Forward-looking statements involve inherent risks and uncertainties. Risk factors that could cause actual results to differ materially from those in forward looking statements include: market prices for commodities, increases in capital or operating costs, construction risks, availability of infrastructure including roads, regulatory and permitting risks, exploitation and exploration successes, continued availability of capital and financing, financing costs, and general economic, market or business conditions. Investors are cautioned that any such statements are not guarantees of future performance and those actual results or developments may differ materially from those projected in the forward-looking statements. For more information on the Company, please review the Company's public filings available at www.sedarplus.ca.

Neither the TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release.

SOURCE Frontier Lithium Inc.

Company Contact Information: Bora Ugurgel, Senior Manager, Investor Relations, 2614 Belisle Drive, Val Caron, Sudbury, Ontario, P3N 1B3 CANADA, T. +001 705.897.7622