First Mining Gold Corp. — AGM Information 2022

May 4, 2022

Notice of 2022 Annual General Meeting of Shareholders

When

Thursday, June 9, 2022 at 10:00 a.m. (Pacific Time)

Where

At our offices, which are located at 1188 West Georgia Street, 3[rd] Floor Boardroom, Vancouver, British Columbia V6E 4A2.

We will cover six items of business at our 2022 annual general meeting (the “ Meeting ”):

• Receive our audited consolidated financial statements for the financial year ended December 31, 2021 and the auditor’s report thereon;

• Fix the number of directors to be elected at the Meeting at five;

• Elect five directors to our board of directors to hold office until the next annual general meeting of shareholders;

• Re-appoint PricewaterhouseCoopers LLP, Chartered Professional Accountants, as our independent auditor for the ensuing year and authorize our directors to set the auditor’s pay;

• Approve the unallocated entitlements under our amended and restated share-based compensation plan, as more particularly described in the accompanying information circular (the “ Circular ”); and

• Transact such other business that is properly brought before the Meeting or any adjournment or adjournments thereof.

Record date

The record date for the Meeting is April 25, 2022. The record date is the date for the determination of the registered holders of our Common Shares entitled to receive notice of, and to vote at, the Meeting and any adjournment or postponement of the Meeting.

Your vote is important

This notice is accompanied by the Circular and either a form of proxy for registered shareholders or a voting instruction form for beneficial (i.e. non-registered) shareholders. If previously requested, a copy of our audited consolidated annual financial statements and the accompanying management’s discussion and analysis (“ MD&A ”) for the year ended December 31, 2021 will also accompany this notice (collectively, the “ Meeting Materials ”). Copies of our annual and/or interim financial statements and MD&A are also available◦under◦our◦SEDAR◦profile◦at◦www.sedar.com,◦on◦our◦website◦at www.firstmininggold.com/investors/reports-filings/financials, or by request made to First Mining Gold Corp. As described in the notice and access notification that we have mailed to our shareholders, we are

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using the notice and access method for delivering this notice and the Meeting Materials to our shareholders, which substantially reduces the paper used in printing this notice and the Meeting Materials, as well as printing and mailing costs. This notice and the Meeting Materials will be available on our website at www.firstmininggold.com/investors/agm/agm-materials and under our SEDAR profile at www.sedar.com.

The Circular contains important information about the Meeting, who can vote and how to vote. Please

read the Circular carefully before voting.

If you will not be attending the meeting in person, we request that you read, date and sign the accompanying proxy and deliver it to our transfer agent, Computershare Investors Services Inc. (“ Computershare ”). If a shareholder does not deliver a proxy to Computershare, Attention: Proxy Department, 100 University Avenue, 8[th] Floor, Toronto, Ontario M5J 2Y1, by 10:00 a.m. (Pacific Time) on Tuesday, June 7, 2022 (or before 48 hours, excluding Saturdays, Sundays and holidays, before any adjournment of the Meeting at which the proxy is to be used), then the shareholder will not be entitled to vote at the Meeting by proxy.

If you would like us to send you a paper copy of the Meeting Materials, please contact Paul Morris, our Director, Investor Relations, at 1.844.306.8827 or by e-mail: info@firstmininggold.com. In order for you to receive the Meeting Materials in advance of the proxy deposit deadline date and the date of the Meeting, we must receive requests for printed copies of the Meeting Materials at least seven business days in advance of the proxy deposit deadline date and time.

BY ORDER OF THE BOARD OF DIRECTORS ,

(signed) “Daniel W. Wilton”

Daniel W. Wilton Chief Executive Officer and Director

Vancouver, British Columbia April 29, 2022

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