IAMGOLD : Côté Gold Site Tour – October 2021

Plant construction at the Côté Gold Project, Canada

Côté Gold - Site Tour

October 19, 2021

TSX: IMG l NYSE: IAG

www.iamgold.com

CÔTÉ GOLD SITE TOUR - OCTOBER 2021

Cautionary Statement

CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING INFORMATION

All information included in this presentation, including any information as to the Company's future financial or operating performance and other statements that express management's expectations or estimates of future performance, including statements in respect of the prospects and/or development of the Company's projects, other than statements of historical fact, constitutes forward-looking information or forward-looking statements within the meaning of applicable securities laws (collectively referred to herein as "forward-looking statements") and such forward-looking statements are based on expectations, estimates and projections as of the date of this presentation. Forward-looking statements are generally identifiable by the use of words such as "may", "will", "should", "continue", "expect", "budget", "forecast", "anticipate", "estimate", "believe", "intend", "plan", "schedule", "guidance", "outlook", "potential", "seek", "targets", "strategy", or "project" or the negative of these words or other variations on these words or comparable terminology. Forward-looking statements in this presentation include, but are not limited to, statements with respect to: the timing for completion of construction at Côté Gold and incremental steps leading to completion of construction; construction costs and site expenditures; the timing and amount of estimated future production; the estimation of mineral reserves and mineral resources; the anticipated realization of mineral reserve and mineral resource estimates; the construction of Côté Gold; the impact of COVID-19 on the Company, including its operations, the project schedule for Côté Gold, key inputs, staffing and contractors; cost pressures, including diesel, power and haulage, the Company's guidance for production; cost of sales; cash costs; all-in sustaining costs; costs of production; depreciation expense; effective tax rate; expected capital expenditures;

operations outlook; expected benefits from the operational improvements and de-risking strategies enacted by the Company; the Company's business recovery plan; the Company's plan to achieve net zero emissions; exploration plans and opportunities; the expected receipt of permits; permitting timelines; sale transactions; the future price of gold and other commodities; foreign exchange rates and currency fluctuations; requirements for additional capital; the Company's capital allocation; and government regulation of mining operations. Forward- looking statements are provided for the purpose of providing information about management's current expectations and plans relating to the future.

The Company cautions the reader that forward-looking statements are necessarily based upon a number of estimates and assumptions that, while considered reasonable by management, are inherently subject to significant business, financial, operational and other risks, uncertainties, contingencies and other factors, including those described below, which could cause actual results, performance or achievements of the Company to be materially different from results, performance or achievements expressed or implied by such forward-looking statements and, as such, undue reliance must not be placed on them. Such risks, uncertainties, contingencies and other factors include, but are not limited to: the Company's business strategies; legal, litigation, legislative, political or economic developments in the jurisdictions in which the Company carries on business; the ongoing impact of COVID-19 and its variants on the Company and its workforce, the availability of labour and contractors, key inputs for the Company and global supply chains; government actions taken in response to COVID-19, including new variants of COVID-19, and any worsening thereof; the volatility of the Company's securities; title disputes; input in the management of certain of the Company's assets by other companies or joint venture partners; the lack of availability of insurance covering all of the risks associated with the Company's operations; unexpected geological conditions; potential shareholder dilution; potential activist engagements; increasing competition and consolidation in the mining sector; the condition and results of the mining industry as a whole, and the gold mining industry in particular; changes in the global prices for gold or other commodities and key inputs required in the mining industry (such as diesel and electricity); changes in tax laws, including mining tax regimes; the failure to obtain in a timely manner from authorities key permits, authorizations or approvals necessary for exploration, development or operations at the Company's operations; the inability to participate in any gold price increase above the cap in any collar transaction entered into in conjunction with a gold sale prepayment arrangement; the availability of necessary capital and impacts on the Company's liquidity levels; access to capital markets and financing; the Company's level of indebtedness; the Company's ability to satisfy covenants under its credit facilities and other debt instruments; changes in interest rates; adverse changes in the Company's credit rating; the Company's choices in capital allocation; effectiveness of the Company's ongoing cost containment efforts; the ability to execute on the Company's de-risking activities and measures to improve operations; risks related to third-party contractors, including reduced control over aspects of the Company's operations and/or the failure of contractors to perform as expected; risks arising from holding derivative instruments; changes in U.S. dollar and other currency exchange rates, interest rates or gold lease rates; capital and currency controls in foreign jurisdictions; assessment of carrying values for the Company's assets, including the ongoing potential for material impairment and/or write-downs of such assets; the speculative nature of exploration and development, including the risks of diminishing quantities or grades of reserves; the fact that reserves and resources, expected metallurgical recoveries, capital and operating costs are estimates which may require revision; the presence of unfavourable content in ore deposits, including clay and coarse gold; inaccuracies in life of mine plans; failure to meet operational targets; geotechnical difficulties; failure of key equipment and technology; security risks, including civil unrest, war or terrorism; information systems security threats and cybersecurity; laws and regulations governing the protection of the environment; employee relations and labour disputes; the maintenance of tailings storage facilities and the potential for a major spill or failure of the tailings facilities due to uncontrollable events, such as extreme and unpredictable weather or seismic events; lack of reliable infrastructure, including access to roads, bridges, power sources and water supplies; physical and regulatory risks related to climate change; attraction and retention of key employees and other qualified personnel; availability and increasing costs associated with mining inputs and labour; the availability of qualified contractors and the ability of contractors to timely complete projects on acceptable terms; the relationship with the communities surrounding the Company's operations and projects; indigenous rights or claims; illegal mining; and the inherent risks involved in the mining industry generally.

Although the Company has attempted to identify important factors that could cause actual results to differ materially from those contained in forward-looking statements, there may be other factors that cause results not to be as anticipated, estimated or intended. The Company disclaims any intention or obligation to update or revise any forward-looking statements whether as a result of new information, future events or otherwise except as required by applicable law.

All amounts in this presentation are expressed in U.S. dollars except as otherwise noted.

CAUTIONARY NON-GAAP PERFORMANCE MEASURES

This presentation contains non-GAAP financial performance measures, including cash costs ("CC") per ounce sold and all-in sustaining costs ("AISC") per ounce sold, on an attributable basis. CC includes mine site operating costs such as mining, processing, administration, royalties, production taxes, and realized derivative gains or losses, exclusive of depreciation, reclamation, capital expenditures and exploration and evaluation costs. AISC includes cost of sales, excluding depreciation expense, and includes sustaining capital expenditures which are required to maintain existing operations, sustaining exploration and evaluation expenses, sustaining lease principal payments, environmental rehabilitation accretion and depreciation, by-product credits, and corporate general and administrative costs. These costs are then divided by the Company's attributable ounces of gold sold by mine sites in commercial production to arrive at CC and AISC per ounce sold. The Company believes that the use of CC and AISC per ounce sold metrics will assist analysts, investors and other stakeholders of the Company in assessing its operating performance and its ability to generate free cash flow. CC and AISC per ounce sold are intended to provide additional information only and do not have any standardized meaning prescribed by IFRS, and are unlikely to be comparable to similar measures presented by other issuers, and should not be considered in isolation or as a substitute for measures of performance prepared in accordance with IFRS. Although the World Gold Council defined an all-in sustaining costs measure in 2013, it is not a regulatory organization, and other companies may calculate this measure differently. These measures are not necessarily indicative of net earnings or cash flow from operating activities as determined under IFRS.

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CÔTÉ GOLD SITE TOUR - OCTOBER 2021

Technical Information and Qualified Persons

QUALIFIED PERSON AND TECHNICAL INFORMATION

The technical and scientific information relating to exploration activities disclosed in this document was prepared under the supervision of and verified and reviewed by Craig MacDougall, P.Geo., Executive Vice President, Growth, IAMGOLD. Mr. MacDougall is a "qualified person" (a "QP") as defined by National Instrument 43-101 - Standards of Disclosure for Mineral Projects ("NI 43-101").

The Mineral Resource and Reserve Estimates contained in this presentation have been prepared in accordance with NI 43-101. The QP responsible for the review and approval of all year-end Mineral Resource and Reserve Estimates for IAMGOLD contained herein is Lisa Ragsdale, Eng., Director, Mining Geology. Ms. Ragsdale has worked in the mining industry for more than 15 years, mainly in operations, project development and consulting. Ms. Ragsdale joined IAMGOLD in January 2018 and acquired her knowledge of the Company's operations and projects through site visits, information reviews, and ongoing communication and oversight of mine site technical service teams or consultants responsible for mineral resource estimates. The technical information has been included herein with the consent and prior review of the above noted QP. The QP has verified the data disclosed, and data underlying the information or opinions contained herein.

Drilling results in this presentation have been prepared in accordance with NI 43-101. The sampling of, and assay data from, drill core is monitored through the implementation of a quality assurance - quality control ("QA-QC") program designed to follow industry best practice. The QP responsible for the supervision of the preparation, verification, and review of these results is Craig MacDougall, P.Geo., Executive Vice President, Growth for IAMGOLD.

For readers to fully understand the technical information contained in this presentation, they should read the relevant technical reports that have been prepared in accordance with NI 43-101 (each, a "Technical Report") in their entirety, including all qualifications, assumptions and exclusions contained therein. Each Technical Report is intended to be read as a whole, and sections should not be read or relied upon out of context. Each Technical Report describes the Mineral Resource and Reserve estimation methodologies and the assumptions used, and to which those estimates are subject. The Company's AIF, which was filed on SEDAR on February 17, 2021 includes details of certain risk factors that could materially affect the potential development of the Mineral Resources and Mineral Reserves and should be considered carefully. A discussion of these and other factors is contained in "Risk Factors" and elsewhere in the Company's AIF.

CAUTIONARY NOTE TO U.S. INVESTORS REGARDING DISCLOSURE OF MINERAL RESERVE AND MINERAL RESOURCE ESTIMATES

The mineral resource and reserve estimates contained in this news release have been prepared in accordance with NI 43-101. These standards are similar to those used by the United States Securities and Exchange Commission (the "SEC") Industry Guide No. 7, as interpreted by the SEC staff. However, the definitions in NI 43-101 differ in certain respects from those under Industry Guide 7. Accordingly, mineral resource and reserve information contained in this news release may not be comparable to similar information disclosed by United States companies. Under the SEC's Industry Guide 7, mineralization may not be classified as a "reserve" unless the determination has been made that the mineralization could be economically and legally produced or extracted at the time the reserve determination is made.

As a result of the adoption of amendments to the SEC's disclosure rules (the "SEC Modernization Rules"), which more closely align its disclosure requirements and policies for mining properties with current industry and global regulatory practices and standards, including NI 43-101, and which became effective on February 25, 2019, the SEC now recognizes estimates of "measured mineral resources", "indicated mineral resources" and "inferred mineral resources." In addition, the SEC has amended definitions of "proven mineral reserves" and "probable mineral reserves" in its amended rules, with definitions that are substantially similar to those used in NI 43-101. Issuers must begin to comply with the SEC Modernization Rules in their first fiscal year beginning on or after January 1, 2021, though Canadian issuers that report in the United States using the Multijurisdictional Disclosure System ("MJDS") may still use NI 43-101 rather than the SEC Modernization Rules when using the SEC's MJDS registration statement and annual report forms.

United States investors are cautioned that while the SEC now recognizes "measured mineral resources", "indicated mineral resources" and "inferred mineral resources" under the SEC Modernization Rules, investors should not assume that any part or all of the mineral deposits in these categories will ever be converted into a higher category of mineral resources or into mineral reserves. These terms have a great amount of uncertainty as to their economic and legal feasibility. Under Canadian regulations, estimates of inferred mineral resources may not form the basis of feasibility or pre-feasibility studies, except in limited circumstances.

Investors are cautioned not to assume that any "measured mineral resources", "indicated mineral resources", or "inferred mineral resources" that the Company reports in this news release are or will be economically or legally mineable. Further, "inferred mineral resources" have a great amount of uncertainty as to their existence and as to their economic and legal feasibility. It cannot be assumed that any part or all of an inferred mineral resource will ever be upgraded to a higher category.

The mineral reserve and mineral resource data set out in this news release are estimates, and no assurance can be given that the anticipated tonnages and grades will be achieved or that the indicated level of recovery will be realized. The Company does not include equivalent gold ounces for by-product metals contained in mineral reserves in its calculation of contained ounces and mineral reserves are not reported as a subset of mineral resources.

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Site Tour Agenda

1. Project Overview
2. Construction Progress Update
3. Mining
4. Processing / TMF / Stockpiles
5. Operational Readiness
6. Community Relations & ESG
7. Project Capital & Operating Costs
8. Exploration District Upside
9. Appendix

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Project Overview

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