OceanaGold : Q2 2023 MD&A

Management Discussion and Analysis

Second Quarter 2023 Results

August 1, 2023

CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING INFORMATION IN MANAGEMENT DISCUSSION & ANALYSIS

This Management Discussion & Analysis contains "forward-looking statements and information" within the meaning of applicable securities laws which may include, but is not limited to, statements with respect to the future financial and operating performance of the Company, its subsidiaries and affiliated companies, its mining projects, the future price of gold, the estimation of mineral reserves and mineral resources, the realisation of mineral reserve and resource estimates, costs of production, estimates of initial capital, sustaining capital, operating and exploration expenditures, costs and timing of the development of new deposits, costs and timing of the development of new mines, costs and timing of future exploration and drilling programs, timing of filing of updated technical information, anticipated production amounts, requirements for additional capital, governmental regulation of mining operations and exploration operations, timing and receipt of approvals, consents and permits under applicable mineral legislation, environmental risks, title disputes or claims, limitations of insurance coverage and the timing and possible outcome of pending litigation and regulatory matters. Often, but not always, forward-looking statements and information can be identified by the use of words such as "may", "plans", "expects", "projects", "is expected", "budget", "scheduled", "potential", "estimates", "forecasts", "intends", "targets", "aims", "anticipates" or "believes" or variations (including negative variations) of such words and phrases, or may be identified by statements to the effect that certain actions, events or results "may", "could", "would", "should", "might" or "will" be taken, occur or be achieved. Forward-looking statements and information involve known and unknown risks, uncertainties and other factors which may cause the actual results, performance or achievements of the Company and/or its subsidiaries and/or its affiliated companies to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements. Such factors include, among others, future prices of gold; general business, economic and market factors (including changes in global, national or regional financial, credit, currency or securities markets), changes or developments in global, national or regional political and social conditions; changes in laws (including tax laws) and changes in GAAP or regulatory accounting requirements; the actual results of current production, development and/or exploration activities; conclusions of economic evaluations and studies; fluctuations in the value of the United States dollar relative to the Canadian dollar, the Australian dollar, the Philippines Peso or the New Zealand dollar; changes in project parameters as plans continue to be refined; possible variations of ore grade or recovery rates; failure of plant, equipment or processes to operate as anticipated; accidents, labour disputes and other risks of the mining industry; political instability or insurrection or war; labour force availability and turnover; adverse judicial decisions, inability or delays in obtaining financing or governmental approvals; inability or delays in the completion of development or construction activities or in the re-commencement of operations; legal challenges to mining and operating permits including the renewed Financial or Technical Assistance Agreement as well as those factors discussed in the section entitled "Risk Factors" contained in the Company's Annual Information Form in respect of its fiscal year-ended December 31, 2022, which is available on SEDAR at www.sedar.comunder the Company's name. Although the Company has attempted to identify important factors that could cause actual actions, events, or results to differ materially from those described in forward-looking statements and information, there may be other factors that cause actual results, performance, achievements, or events to differ from those anticipated, estimated or intended. Also, many of the factors are outside or beyond the control of the Company, its officers, employees, agents, or associates. Forward-looking statements and information contained herein are made as of the date of this Management Discussion & Analysis and, subject to applicable securities laws, the Company disclaims any obligation to update any forward-looking statements and information, whether as a result of new information, future events, or results or otherwise. There can be no assurance that forward-looking statements and information will prove to be accurate, as actual results and future events could differ materially from those anticipated in such statements. Accordingly, readers should not place undue reliance on forward-looking statements and information due to the inherent uncertainty therein. All forward-looking statements and information made herein are qualified by this cautionary statement. This Management Discussion & Analysis may use the terms "Measured", "Indicated" and "Inferred" Resources. U.S. investors are advised that while such terms are recognised and required by Canadian regulations, the Securities and Exchange Commission does not recognise them. "Inferred Resources" have a great amount of uncertainty as to their existence and as to their economic and legal feasibility. It cannot be assumed that all or any part of an Inferred Resources will ever be upgraded to a higher category. Under Canadian rules, estimates of Inferred Resources may not form the basis of feasibility or other economic studies. U.S. investors are cautioned not to assume that all or any part of Measured or Indicated Resources will ever be converted into reserves. U.S. investors are also cautioned not to assume that all or any part of an Inferred Resource exists or is economically or legally mineable. This document does not constitute an offer of securities for sale in the United States or to any person that is, or is acting for the account or benefit of, any U.S. person (as defined in Regulation S under the United States Securities Act of 1933, as amended (the "Securities Act") ("U.S. Person"), or in any other jurisdiction in which such an offer would be unlawful.

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TECHNICAL DISCLOSURE

All Mineral Reserves and Mineral Resources were calculated as of 31 December 2022 and have been calculated and prepared in accordance with National Instrument 43-101 of the Canadian Securities Administrators ("NI 43-101").

The exploration information contained in this MD&A has been reviewed and approved by C Feebrey; Mineral Resources for Macraes underground operations have been reviewed and approved by M Grant; Mineral Reserves for Macraes open pits have been reviewed and approved by P Doelman. The Mineral Reserves for Macraes underground have been reviewed and approved by S Mazza; Mineral Resources for Waihi's Martha open pit and Wharekirauponga Underground have been reviewed and approved by J Moore; Mineral Resources for Waihi's Gladstone open pit and Martha Underground have been reviewed and approved by L Crawford-Flett. The Underground Mineral Reserves for Waihi have been reviewed and approved by D Townsend. Mineral Resources for Haile open pit and underground have been reviewed and approved by J Moore. The Open-pit Reserves for Haile have been reviewed by G Hollett and the Underground Reserves by B Drury. Mineral Reserves for Didipio underground have been reviewed and approved by P Jones. The Mineral Resources for Didipio have been reviewed and approved by J Moore.

The above persons are employees of OceanaGold Corporation or its fully owned subsidiaries, and are "qualified persons" for the purposes of NI 43-101.

Readers should refer to the Company's most recent Annual Information Form and Resources and Reserves statement, as well as other continuous disclosure documents filed by the Company available at sedar.com for further information on the Mineral Reserves and Mineral Resources.

For further scientific and technical information relating to the Haile mine, the Waihi mine, the Macraes mine and the Didipio mine, please refer to the following NI 43-101 compliant technical reports available at sedar.com under the Company's name:

1. "NI 43-101 Technical Report, Macraes Gold Mine, Otago, New Zealand" dated 14 October 2020, prepared by D. Carr, Chief Metallurgist, of OceanaGold Management Pty Limited, T. Cooney, previously General Manager of Studies of OceanaGold Management Pty Limited, P. Doelman, Tech Services and Project Manager, S. Doyle, previously Principal Resource Geologist of Oceana Gold (New Zealand) Limited, and P. Edwards, Senior Project Geologist, of Oceana Gold (New Zealand) Limited;
2. "Technical Report for the Didipio Gold / Copper Operation Luzon Island" dated 31 March 2022, prepared by D. Carr, Chief Metallurgist, P. Jones, Group Engineer and J. Moore, Chief Geologist, each of OceanaGold Management Pty Limited;
3. "Waihi District Study - Martha Underground Feasibility Study NI 43-101 Technical Report" dated 31 March 2021, prepared by T. Maton, Study Manager of Oceana Gold (New Zealand) Limited, and P. Church, previously Principal Resource Development Geologist, of Oceana Gold (New Zealand) Limited, and D. Carr, Chief Metallurgist, of OceanaGold Management Pty Limited; and
4. "NI 43-101 Technical Report Haile Gold Mine Lancaster County, South Carolina" dated 31 March 2022, prepared by D. Carr, Chief Metallurgist, G. Hollett, Group Mining Engineer, and J. Moore, Chief Geologist, each of OceanaGold Management Pty Limited, Michael Kirby of Haile Gold Mine, Inc., J. Poeck, M. Sullivan, D. Bird, B. S. Prosser and J. Tinucci of SRK Consulting, J. Newton Janney-Moore and W. Kingston of Newfields and L. Standridge of Call and Nicholas.

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Second Quarter Highlights

• On track to meet full-year 2023 consolidated production, cost and capital guidance.
• 12MMA total recordable injury frequency rate of 3.5 per million hours worked.
• Consolidated production of 130,055 ounces of gold and 3,400 tonnes of copper.
• All-InSustaining Costs ("AISC") of $1,318 per ounce on gold sales of 139,071 ounces.
• Free Cash Flow of $72.3 million.
• Revenue of $301 million, EBITDA of $153 million and NPAT of $69 million.
• Adjusted earnings of $0.10 per share and operating cash flow of $0.21 per share.
• Record first half revenue of $545 million and EBITDA of $253 million.
• First half 2023 NPAT of $108 million.
• Net debt of $136 million as at June 30, 2023, at a leverage ratio of 0.34 times.
• Haile underground on track, with first ore to the mill expected in the fourth quarter of 2023.
• Obtained regulatory approval for a third drill rig at Wharekirauponga, drilling began in July.
• Semi-annualdividend of $0.01 approved by the Board, to be paid October 6, 2023.

Period ended 30 June 2023	Q2 2023	YTD 2023
(US$m)
Gold Production (koz)	130.1	248.2
Copper Production (kt)	3.4	6.9
All-in Sustaining Costs ($/oz)	1,318	1,429
Revenue	301.0	544.9
EBITDA (excluding impairment expense)	152.5	252.5
Adjusted Net Profit / (Loss) After Tax	70.4	110.5
Net Profit/(Loss) After Tax	68.6	107.5
Free Cash Flow	72.3	55.9
Earnings per share - fully diluted	$0.09	$0.15
Adjusted earnings per share - fully diluted	$0.10	$0.15
Cash flow per share (before working capital movements) - fully diluted	$0.21	$0.36

Notes:

• All numbers in this document are expressed in USD unless otherwise stated. Adjusted Net Profit/(Loss), Cash Costs, All-In Sustaining Costs, All-In Sustaining Margin, EBITDA and Free Cash Flow are non-GAAP measures. Refer to the Accounting & Controls section of this report for an explanation.
• Cash Costs and All-In Sustaining Costs are reported on ounces sold and net of by-product credits.
• Consolidated All-in Sustaining Costs are inclusive of Corporate general and administrative expenses; site All-in Sustaining Costs are exclusive of Corporate general and administrative expenses.
• Fully diluted cash flow per share before working capital movements is calculated as the Net cash provided by / (used in) operating activities adjusted for changes in working capital then divided by the adjusted weighted average number of common shares.

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Results for the quarter ended June 30, 2023

Health and Safety

OceanaGold reported a 12MMA Total Recordable Injury Frequency Rate ("TRIFR") of 3.5 per million hours at the end of the second quarter of 2023. There were 18 recordable injuries during the second quarter, 7 of which were hand injuries. This compared to 3 recordable injuries in the previous quarter.

In response to this significant increase in recordable injuries, the operations have taken targeted actions to address, including a "Safe Hands" campaign initiated in the second quarter to focus on hand injury risk.

As 6 of the 18 injuries occurred at Didipio, a site-wide 'Safety Stop' at Didipio took place in May where all employees and contractors came together to discuss safety performance. Feedback from the session was very positive with particularly powerful messaging delivered by members of the workforce.

A refresh of our safety behaviour program also commenced in the second quarter with specifically designed safety engagement sessions across all sites scheduled for completion by the end of the third quarter of 2023.

Work also continues on critical control and hazardous energy management, with a refresh of the "Stop and Think" processes on track for completion next quarter.

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