Cameco Corporation 2018 Annual information form March 29, 2019 Contents Important information about this document ............................................................................................. 1 About Cameco ............................................................................................................................................. 4 Operations and projects ........................................................................................................................... 21 Uranium – Tier-one operations ............................................................................................................... 22 Uranium – Tier-two curtailed operations ................................................................................................. 68 Uranium – advanced projects ................................................................................................................. 70 Fuel services – refining ........................................................................................................................... 72 Fuel services – conversion and fuel manufacturing ................................................................................ 73 Mineral reserves and resources ............................................................................................................... 75 Sustainable development ......................................................................................................................... 81 The regulatory environment ..................................................................................................................... 90 Risks that can affect our business .......................................................................................................... 97 Legal proceedings ................................................................................................................................... 117 Investor information ................................................................................................................................ 118 Governance .............................................................................................................................................. 123 Appendix A ............................................................................................................................................... 128 Important information about this document This annual information form (AIF) for the year ended December 31, 2018 provides important information about Cameco Corporation. It describes our history, our markets, our operations and projects, our mineral reserves and resources, sustainability, our regulatory environment, the risks we face in our business and the market for our shares, among other things. It also incorporates by reference: • our management’s discussion and analysis (MD&A) for the year ended Throughout this document, the terms we, December 31, 2018 (2018 MD&A), which is available on SEDAR us, our, the company and Cameco mean (sedar.com) and on EDGAR (sec.gov) as an exhibit to our Form 40-F Cameco Corporation and its subsidiaries. • our audited consolidated financial statements for the year ended December 31, 2018 (2018 financial statements), which is also available on SEDAR and on EDGAR as an exhibit to our Form 40-F. We have prepared this document to meet the requirements of Canadian securities laws, which are different from what United States (US) securities laws require. Reporting currency and financial information Unless we have specified otherwise, all dollar amounts are in Canadian dollars. Any references to $(US) mean US dollars. The financial information in this AIF has been presented in accordance with International Financial Reporting Standards (IFRS). Caution about forward-looking information Our AIF and the documents incorporated by reference include statements and information about our expectations for the future. When we discuss our strategy, plans and future financial and operating performance, or other things that have not yet taken place, we are making statements considered to be forward-looking information or forward-looking statements under Canadian and US securities laws. We refer to them in this AIF as forward-looking information. Key things to understand about the forward-looking information in this AIF: • It typically includes words and phrases about the future, such as anticipate, believe, estimate, expect, plan, will, intend, goal, target, forecast, project, strategy and outlook (see examples on page 2). • It represents our current views, and can change significantly. • It is based on a number of material assumptions, including those we have listed below, which may prove to be incorrect. • Actual results and events may be significantly different from what we currently expect, due to the risks associated with our business. We list a number of these material risks below. We recommend you also review other parts of this document, including Risks that can affect our business starting on page 97, and our 2018 MD&A, which include a discussion of other material risks that could cause actual results to differ significantly from our current expectations. Forward-looking information is designed to help you understand management’s current views of our near and longer term prospects, and it may not be appropriate for other purposes. We will not necessarily update this information unless we are required to by securities laws. 2018 ANNUAL INFORMATION FORM Page 1 Examples of forward-looking information in this AIF • our expectations about 2019 and future global uranium supply, • the discussion of our expectations relating to our Canada consumption, demand, prices, contracting volumes and number Revenue Agency (CRA) transfer pricing dispute, including that of reactors, including the discussion under the heading Market the Tax Court of Canada (Tax Court) ruling will be upheld on overview and developments appeal and our estimate of the amount and timing of expected • our belief that the current backlog of long-term contracting cash taxes and transfer pricing penalties presents a substantial opportunity • our expectations for future tax payments and rates, including • our expectation about 2019 and future consumption for effective tax rates conversion services • future plans and expectations for uranium properties, advanced • the discussion under the heading Marketing framework – projects, and fuel services operating sites balanced contract portfolio, including our belief that using the • estimates of operating and capital costs and mine life for our marketing framework will create long-term value for tier one uranium operations shareholders • estimated decommissioning costs for uranium properties and • expectations for repayment of our $500 million debenture fuel services operating sites maturing in 2019 • the discussion of Joint Venture Inkai LLP’s (JV Inkai) expansion • our expectations relating to care and maintenance costs plans for a 10.4 million pound per year operation • our expectations relating to 2019 uranium purchases, including • our mineral reserve and resource estimates our belief that the uranium available in the spot market will not • production estimates at the Cigar Lake and Inkai operations be enough to satisfy long-term demand • our expectation that the US Department of Energy (DOE) will • our belief that our actions in reducing supply and streamlining make available a portion of its excess uranium inventory over operations will shield the company from the nearer term risks the next two decades we face and will reward shareholders for their continued • our expectation that production at McArthur River/Key Lake will patience and support of our strategy to build long-term value be the first of our operations to restart once we see the appropriate market signals, including the potential restart any time after 2019 Material risks • actual sales volumes or market prices for any of our products • our mineral reserve and resource estimates are not reliable, or or services are lower than we expect for any reason, including there are unexpected or challenging geological, hydrological or changes in market prices, loss of market share to a competitor mining conditions or trade restrictions • we are affected by environmental, safety and regulatory risks, • we are adversely affected by changes in currency exchange including increased regulatory burdens or delays rates, interest rates, royalty rates, or tax rates • necessary permits or approvals from government authorities • our production costs are higher than planned, or our cost cannot be obtained or maintained reduction strategies are unsuccessful, or necessary supplies • we are affected by political risks are not available, or not available on commercially reasonable • we are affected by terrorism, sabotage, blockades, civil unrest, terms social or political activism, accident or a deterioration in political • our strategies are unsuccessful or have unanticipated support for, or demand for, nuclear energy consequences • we are impacted by changes in the regulation or public • our estimates of production, purchases, cash flow, costs, perception of the safety of nuclear power plants, which decommissioning, reclamation expenses, or our tax expense adversely affect the construction of new plants, the relicensing prove to be inaccurate of existing plants and the demand for uranium • we are unable to enforce our legal rights under our existing