Brokered LIFE Private Placement is Oversubscribed

London, September 25th, 2026. Orosur Mining Inc. (“Orosur” or the “Company”) (TSX-V/AIM:OMI) is pleased to announce that, further to its news release dated September 22, 2026, the Company’s previously announced “best efforts” private placement (the “Base Offering”) is oversubscribed and fully allocated. Pursuant to the Base Offering, the Company intends to raise gross proceeds of up to C$14,000,000 through the sale of up to 43,750,000 units of the Company (the “Units”) at a price of C$0.32 (being approximately GBP £0.17) per Unit (the “Offering Price”). Red Cloud Securities Inc. (the “Agent”) is acting as sole agent and bookrunner, together with U.K. corporate brokers Turner Pope Investments (TPI) Ltd. and Greenwood Capital Partners Limited, in connection with the Offering (as herein defined).

Orosur Executive Chairman Louis Castro commented:

“We are delighted at the take up of the Offering and the oversubscription in difficult market conditions. We appreciate the support of existing and new investors. The proceeds will be spent almost exclusively on drilling at the Company’s Anza project in Colombia, including at our most recent target at El Cedro. The funds will allow us to start to show the true potential of the project”

Each Unit will consist of one common share of the Company (each, a "Common Share") and one-half of one common share purchase warrant (each whole warrant, a "Warrant"). Each whole Warrant shall entitle the holder to purchase one common share of the Company (each, a "Warrant Share", and the Warrant Shares underlying the Warrants together with the Common Shares to be referred to as the “Underlying Securities”) at a price of US$0.32 (being approximately C$0.45 and approximately GBP £0.24) at any time during the period beginning on the date that is 61 days following the Closing Date (as herein defined) and ending on the date which is 24 months following the Closing Date.

The Company has also granted the Agent the option, exercisable in full or in part, up to 48 hours prior to the Closing Date, to sell up to an additional 6,250,000 Units at the Offering Price for up to an additional C$2,000,000 in gross proceeds (the "Agent’s Option", and together with the Base Offering, the “Offering”).

The Company intends to use the net proceeds of the Offering, which should take us into late 2027, principally to advance the Company's Anzá exploration project in Colombia as well as for general working capital and corporate purposes.

The Offering is scheduled to close on or around October 6, 2026 (the “Closing Date”), or such other date as the Company and the Agent may agree and is subject to certain conditions including, but not limited to, receipt of all necessary approvals including the approval of the TSX Venture Exchange and admission of the Common Shares to the AIM Market of London Stock Exchange plc.

There is an offering document (the “Offering Document”) related to the Offering in Canada that can be accessed under the Company’s profile at www.sedarplus.ca and on the Company’s website at www.orosur.ca. Prospective investors in Canada should read the Offering Document before making an investment decision.