Security Class Holder Account Number Form of Proxy - Annual General and Special Meeting to be held on April 26, 2023 This Form of Proxy is solicited by and on behalf of Management. Notes to proxy 1. Every holder has the right to appoint some other person or company of their choice, who need not be a holder, to attend and act on their behalf at the meeting or any adjournment or postponement thereof. If you wish to appoint a person or company other than the Management Nominees whose names are printed herein, please insert the name of your chosen proxyholder in the space provided (see reverse). 2. If the securities are registered in the name of more than one owner (for example, joint ownership, trustees, executors, etc.), then all those registered should sign this proxy. If you are voting on behalf of a corporation or another individual you may be required to provide documentation evidencing your power to sign this proxy with signing capacity stated. 3. This proxy should be signed in the exact manner as the name(s) appear(s) on the proxy. 4. If a date is not inserted in the space provided on the reverse of this proxy, it will be deemed to bear the date on which it was mailed to the holder by Management. 5. The securities represented by this proxy will be voted as directed by the holder, however, if such a direction is not made in respect of any matter, and the proxy appoints the Management Nominees listed on the reverse, this proxy will be voted as recommended by Management. 6. The securities represented by this proxy will be voted in favour, or withheld from voting, or voted against each of the matters described herein, as applicable, in accordance with the instructions of the holder, on any ballot that may be called for. If you have specified a choice with respect to any matter to be acted on, the securities will be voted accordingly. 7. This proxy confers discretionary authority in respect of amendments or variations to matters identified in the Notice of Meeting and Management Information Circular or other matters that may properly come before the meeting or any adjournment or postponement thereof, unless prohibited by law. 8. This proxy should be read in conjunction with the accompanying documentation provided by Management. Proxies submitted must be received by 3:30 p.m. (Vancouver time) on April 24, 2023. VOTE USING THE TELEPHONE OR INTERNET 24 HOURS A DAY 7 DAYS A WEEK! To Vote Using the Telephone • Call the number listed BELOW from a touch tone telephone. 1-866-732-VOTE (8683) Toll Free To Vote Using the Internet • Go to the following web site: www.investorvote.com • Smartphone? Scan the QR code to vote now. If you vote by telephone or the Internet, DO NOT mail back this proxy. Voting by mail may be the only method for securities held in the name of a corporation or securities being voted on behalf of another individual. Voting by mail or by Internet are the only methods by which a holder may appoint a person as proxyholder other than the Management Nominees named on the reverse of this proxy. Instead of mailing this proxy, you may choose one of the two voting methods outlined above to vote this proxy. To vote by telephone or the Internet, you will need to provide your CONTROL NUMBER listed below. CONTROL NUMBER ------- Fold ------- Fold

------- Fold ------- Fold Appointment of Proxyholder I/We being holder(s) of securities of Ero Copper Corp. (the “Company”) hereby appoint: Christopher Noel Dunn, Chairman, or failing this person, David Strang, Chief Executive Officer, or failing this person, Wayne Drier, Chief Financial Officer (the "Management Nominees") OR Print the name of the person you are appointing if this person is someone other than the Management Nominees listed herein. as my/our proxyholder with full power of substitution and to attend, act and to vote for and on behalf of the holder in accordance with the following direction (or if no directions have been given, as the proxyholder sees fit) and on all other matters that may properly come before the Annual General and Special Meeting of shareholders of the Company to be held at the Bowden Room at the Rosewood Hotel Georgia, 801 West Georgia Street, Vancouver, British Columbia V6C 1P7 on April 26, 2023 at 3:30 p.m. (Vancouver time) and at any adjournment or postponement thereof. VOTING RECOMMENDATIONS ARE INDICATED BY HIGHLIGHTED TEXT OVER THE BOXES. 1. Number of Directors To set the number of Directors at ten. For Against 2. Election of Directors 01. Christopher Noel Dunn For Withhold 02. David Strang For Withhold 03. Jill Angevine For Withhold 04. Lyle Braaten 05. Steven Busby 06. Dr. Sally Eyre 07. Robert Getz 08. Chantal Gosselin 09. John Wright 10. Matthew Wubs 3. Appointment of Auditors Appointment of KPMG LLP, Chartered Professional Accountants, as Auditors of the Company for the ensuing year and authorizing the Directors to fix their remuneration. For Withhold 4. Stock Option Plan Authorize and approve the Company’s Stock Option Plan, including amendments thereto, and the unallocated options issuable thereunder. For Against 5. Share Unit Plan To authorize and approve the Company’s Share Unit Plan, including amendments thereto, and the unallocated units issuable thereunder. For Against 6. Advisory Vote on Executive Compensation To approve a non-binding advisory “say on pay” resolution accepting the Company’s approach to executive compensation. For Against Signature of Proxyholder I/We authorize you to act in accordance with my/our instructions set out above. I/We hereby revoke any proxy previously given with respect to the Meeting. If no voting instructions are indicated above, and the proxy appoints the Management Nominees, this Proxy will be voted as recommended by Management. Signature(s) Date Interim Financial Statements - Mark this box if you would like to receive Interim Financial Statements and accompanying Management’s Discussion and Analysis by mail. Annual Financial Statements - Mark this box if you would like to receive the Annual Financial Statements and accompanying Management’s Discussion and Analysis by mail. Information Circular - Mark this box if you would like to receive the Information Circular by mail for the next securityholders' meeting. If you are not mailing back your proxy, you may register online to receive the above financial report(s) by mail at www.computershare.com/mailinglist. 3 4 9 7 9 8 A R 1E P P Q