IAMGOLD : Corporate Presentation – October 2021

Sunrise over the Côté Gold Project, Canada

Corporate Presentation

October 2021

TSX: IMG l NYSE: IAG

www.iamgold.com

OCTOBER 2021 CORPORATE PRESENTATION

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. For example, forward-looking statements in this presentation include, without limitation, but are not limited to, statements with respect to: construction costs and site expenditures; 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; the timing and amount of estimated future production; costs of production; depreciation expense; effective tax rate; expected capital expenditures; operations outlook; the disclosure of an initial resource at Gosselin; the Company's expected decision with respect to its proposed future heap leach operation at Essakane; 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; the resumption of strategic mine development activities; development and expansion projects; exploration; impairment assessments and estimates; 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; the estimation of mineral reserves and mineral resources; the realization of mineral reserve and mineral resource estimates; the construction of Côté Gold; 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. 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", "transformational", "best-in-class","top-tier", "seek", "targets", "strategy", "superior" or "project" or the negative of these words or other variations on these words or comparable terminology.

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. Forward-looking statements are also based on numerous material factors and assumptions, including as described in this presentation, including with respect to: the Company's present and future business strategies; operations performance within expected ranges; anticipated future production and cash flows; local and global economic conditions and the environment in which the Company will operate in the future; the price of gold, copper, silver and other key commodities; projected mineral grades; international exchanges rates; anticipated capital and operating costs; the availability and timing of required governmental and other approvals for the construction of the Company's projects.

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

IAMGOLD uses certain non-GAAP financial performance measures in this presentation, which are described below:

Cash costs ("CC") per ounce sold and all-in sustaining costs ("AISC") per ounce sold, on an attributable basis, are non-GAAP performance measures. Cash costs include 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 include 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. For a reconciliation of these measures please refer to the "Non-GAAP Performance Measures" section in the most recent MD&A filed on SEDAR at www.sedar.com.

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OCTOBER 2021 CORPORATE PRESENTATION

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 National Instrument 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. Ms. Ragsdale is considered a QP for the purposes of NI 43-101 with respect to the mineralization being reported on. 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. Mr. MacDougall is a QP as defined by NI 43-101.

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 Investors Concerning Estimates of Measured and Indicated Resources

This presentation uses the terms "measured resources" and "indicated resources". We advise investors that while such terms are recognized and required by Canadian regulations, the United States Securities and Exchange Commission (the "SEC") does not recognize them. Investors are cautioned not to assume that any part or all of mineral deposits in these categories will ever be converted into reserves.

Exploration Target Potential: The potential quantity and grade of the exploration targets referred to are conceptual in nature and insufficient exploration work has been completed to define a Mineral Resource. The property will require significant future exploration to advance to a resource stage and there can be no certainty that the exploration target will result in a Mineral Resource being delineated. The exploration targets are consistent with similar deposits in the area, deposit models or derived from initial drilling results.

Cautionary Note to Investors Concerning Estimates of Inferred Resources

This presentation also uses the term "inferred resources". We advise investors that while this term is recognized and required by Canadian regulations, the SEC does not recognize it. "Inferred resources" have a great amount of uncertainty as to their existence and great uncertainty as to their economic and legal feasibility. It cannot be assumed that all or any part of an inferred Mineral Resource will ever be upgraded to a higher category. Under Canadian rules, estimates of Inferred Mineral Resources may not form the basis of feasibility or pre-feasibility studies, except in rare cases. Investors are cautioned not to assume that part or all of an inferred resource exists, or is economically or legally mineable.

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OCTOBER 2021 CORPORATE PRESENTATION

IAMGOLD - Positioned for Profitable Growth

I	Diversified Operating	•	Operating in three regions (North/South America, W. Africa) with 2021 guidance of 565-605koz1
Portfolio	•	Company-wide operational excellence program underway

II

Culture of	•	Zero Harm® commitment and focus on safety, while building strong community partnerships
•	Rapid COVID-19response with extensive steps taken to protect the health & safety of employees,
Accountable Mining
	contractors and host communities

III	Compelling Value &	• Peer-leading organic growth profile targeting gold production of >1 Mozpa by 2025 as Côté Gold
brought online with a long-term AISC target of <$1,000/oz2,3
	Production Growth	• Value opportunity relative to peers on P/CF, EV/EBITDA and P/NAV metrics
		• Strong liquidity position of close to $1.3B, including $830M in cash & cash equivalents, and
IV
Financial Capacity	improving operating margins at existing operations4
		• Adequate financial capacity to implement ongoing development of Côté Gold

V

Robust Pipeline	•	Near-sitedistrict growth: Saramacca (Rosebel), Gosselin (Côté), Fayolle / Rouyn (Westwood)
of Projects	•	Re-seedingthe pipeline with long-term growth: Bambouk and Chibougamau districts

1.	Refer to IAMGOLD news release dated August 4, 2021. 2. Based on 2025 target production range of 1.0-1.3 Moz, not intended to be guidance.	4
3.	Forward-looking statement. Please refer to the Cautionary Statement. 4. As at June 30, 2021; excludes restricted cash of $37.8 million.

OCTOBER 2021 CORPORATE PRESENTATION

1. Diversified Operating Portfolio

Developing High Potential Mining Districts in Key Regions

M&I RESOURCES

ATTRIBUTABLE1,2

CHIBOUGAMAU

Ontario	DISTRICT	Nelligan
	Grand
Côté	Duc	Monster
Fayolle	Lake
CÔTÉ Gold	Westwood
DISTRICT	Rouyn	Québec
Gosselin ABITIBI

DISTRICT

NORTH AMERICA REGION

Rosebel

(incl. Saramacca)

French

Suriname ROSEBEL Guiana

DISTRICT

SOUTH AMERICA REGION

IAMGOLD Mining District

Operating Mine

Construction /

Development Project

Advanced Exploration

Senegal		ESSAKANE
Mali	DISTRICT
Boto Gold BAMBOUK	Essakane
	DISTRICT

Karita Diakha-	Burkina Faso
Siribaya

Guinea

WEST AFRICA REGION

34%28%

North	West Africa
America

23.9 Moz

38%

South America

P&P RESERVES

ATTRIBUTABLE1,2

38%32%

North	West Africa
America

13.9 Moz

30%

South America

1.	Mineral reserve and resource estimate as at December 31, 2020. Mineral resources are inclusive of reserves.	5
2.	P&P reserves and M&I resources estimated using a $1,200/oz and $1,500/oz gold price, respectively. Not including attributable inferred resources of 11.3 Moz.