Canada Uranium Mines and Mills: Athabasca Basin Guide

Reference article · Updated 2026-11-06

Key facts

Canadian production in 2024 was about 14,300 tU, around 24% of world output; about 90% is exported (World Nuclear Association).
McArthur River/Key Lake (7,808 tU) and Cigar Lake (6,501 tU) were the two largest uranium mines in the world in 2024.
Cigar Lake's reserves average 15.9% U3O8; McArthur River's ore averaged 6.48% U3O8 at end-2025.
Rabbit Lake has been in care and maintenance since 2016, and McArthur River was suspended from January 2018 until production resumed in 2022.

The Athabasca Basin and Canada's output

Almost all Canadian uranium production comes from northern Saskatchewan. The earlier Athabasca mines (Rabbit Lake, Cluff Lake and Key Lake) supplied most output until about 2000, and the mines that started from 1999, McArthur River and Cigar Lake, now supply most of it. Production totals have varied widely with market conditions: the World Nuclear Association lists 16,541 t U₃O₈ in 2016, 4,581 t in 2020 and 8,668 t in 2022, before output of about 14,300 tU in 2024. The deposits are unconformity-related, with very high grades; see the mining map for how they compare to other deposit types.

The five licensed mines and mills

The Canadian Nuclear Safety Commission (CNSC) lists five operating uranium mines and mills, all in Saskatchewan. Their status differs substantially.

Site	Role	Notes
McArthur River	Underground mine	Cameco 69.8% and operator, Orano 30.2%; ore averaged 6.48% U₃O₈ at end-2025
Key Lake	Mill	Processes McArthur River ore; Cameco-operated; the Key Lake open pits are mined out
Cigar Lake	Underground mine	Cameco is the largest owner and operator; Orano holds a share; started 2014
McClean Lake	Mill and mine	Orano Canada 77.5%, Denison 22.5%; mills Cigar Lake ore
Rabbit Lake	Mine and mill	In care and maintenance since 2016

Cigar Lake and McArthur River: why very high grade matters

Cigar Lake began mining in 2014; jet boring started in December 2013 and the first ore slurry reached McClean Lake in March 2014. Its ore grade is 15.9% U₃O₈ in proven and probable reserves according to the World Nuclear Association.

The ore is processed at Orano's McClean Lake mill, which was licensed at 10,900 t U₃O₈ per year in 2016, and the licence was later renewed to 2027. Cigar Lake output reached 8,200 t U₃O₈ in 2017, was suspended in March 2020 for the pandemic, restarted in September 2020, suspended again in December 2020 and restarted in April 2021.

McArthur River commenced production in 1999. The mine was suspended in January 2018 because of weak prices, with output falling from 7,303 t U₃O₈ in 2017 to 90 t in 2018. Production resumed in 2022 and, in November 2022, ore was milled at Key Lake for the first time since the shutdown. High grades imply low volumes of tailings per tonne of uranium, but also require radiation protection measures for workers handling the ore, which is why both mines use remote or specialised techniques.

Rabbit Lake and the end of the older generation

Rabbit Lake was discovered in 1968 and entered production in 1975. Output fell from 1,912 t in 2015 to 505 t in 2016 before the mine and mill were placed on care and maintenance in 2016, with a C$124 million write-off in the second quarter of that year. No production has been recorded since. Key Lake produced no uranium from its own pits after 2002; it now mills ore from elsewhere. Cluff Lake, which began production in 1980, has been mined out. The shift from older, lower-grade mines to the high-grade ones is the main structural change of the past 25 years.

Reading Canadian numbers: ownership, share and operator

Canadian uranium statistics can be read three ways, and they differ. Total mine output counts all the uranium from a site; operator or owner share counts only the portion attributable to a company; and mill output counts the uranium concentrate produced at a mill, which may include ore from another mine. McArthur River ore, for example, is milled at Key Lake, and Cigar Lake ore at McClean Lake. When Cameco reports its share of McArthur River/Key Lake (69.8%) or Cigar Lake, the number is lower than the site total in the World Nuclear Association's mine ranking.

Operating status also changes the interpretation of the series. The very low Canadian totals of 2020 (4,581 t U₃O₈) reflect the pandemic suspensions at Cigar Lake and McClean Lake and the continued McArthur River shutdown, not a loss of resources. The recovery to about 14,300 tU in 2024 followed the 2022 resumption of McArthur River production and the 2021 restart of Cigar Lake. Both mines also produce within annual licensed limits that the CNSC can change.

Regulation by the CNSC

The CNSC licenses uranium mines and mills across their life: site preparation, construction, operation, decommissioning and abandonment. Licence decisions listed by the World Nuclear Association include the 2015 approval of Key Lake mill output of 11,350 t U₃O₈ a year and the May 2016 licensing of the McClean Lake capacity increase. In 2023 the CNSC renewed Cameco's licences for Key Lake, McArthur River and Rabbit Lake for 20 years, with the first two to 2043 and Rabbit Lake to 2038, according to a news report.

Newer projects are advancing through the process: the World Nuclear Association records that the CNSC licensed the Phoenix project in February 2026 and site preparation and construction for Arrow in March 2026, while the Patterson Lake South application (April 2023) remained under review. Mining by the SABRE method resumed at McClean Lake North in June 2025. For international comparison see regulation.

Legacy sites: Elliot Lake, Port Radium and Beaverlodge

Canada's early uranium industry produced legacy sites that remain subject of long-term management. At Port Radium in the Northwest Territories, Eldorado began operations in the early 1930s to recover radium. At Beaverlodge in Saskatchewan, Eldorado Nuclear began mining in 1953, and production ceased in 1982.

At Elliot Lake in Ontario, the first discovery was in 1953 and the last of the lower-grade mines closed in 1996; rehabilitation covers 12 mines and ten mill sites, with much work handled by Rio Algom and Denison. Principles of tailings management and long-term care are explained on uranium mill tailings, and relations with Indigenous communities in northern mining are covered on uranium mining and Indigenous peoples.

What to watch

Because Canadian production comes from few mines, changes at one site matter globally. Items to track include annual guidance from operators, CNSC licensing decisions, in-situ projects in the Basin (such as Phoenix), and ownership changes. Ownership percentages move: the World Nuclear Association reports that Idemitsu divested its Cigar Lake interest in May 2022 and TEPCO its interest in July 2026. The page on ISL explains how a method new to the Athabasca Basin differs from underground mining.

Frequently asked questions

Which Canadian uranium mines are operating?

McArthur River and Cigar Lake are the two large producing mines; ore from McArthur River is milled at Key Lake and Cigar Lake ore at McClean Lake. Rabbit Lake has been in care and maintenance since 2016.

How much of world uranium comes from Canada?

About 24% in 2024, or about 14,300 tU, according to the World Nuclear Association.

Who regulates uranium mining in Canada?

The Canadian Nuclear Safety Commission licenses mines and mills through their life cycle.

Why was McArthur River suspended in 2018?

Cameco announced the suspension in November 2017 because of weak uranium prices, and production resumed in 2022.

What are the legacy uranium sites in Canada?

Examples include Port Radium in the Northwest Territories, Beaverlodge in Saskatchewan and the Elliot Lake district in Ontario, all with long-term rehabilitation or monitoring programmes.