Which Canadian stocks were the best and worst performers in May?
The Morningstar Canada Large-Mid Cap Index rose 5.4% in May amid a rally in the industrials sector. The large-mid index tracks the performance of the top 90% of the Canadian investable universe by market cap, and each month we screen from among the stocks in this index to find the best- and worst-performing companies.
Data in this article is sourced from Morningstar Direct.
The following are May’s top and bottom Canadian stocks:
Best-Performing Stocks of May 2025
Worst-Performing Stocks of May 2025
Metrics for the Best-Performing Stocks
Air Canada
- Sector: Industrials
- Industry: Airlines
- Economic Moat: None
Air Canada jumped 37.4% in May, lifting shares 5.5% over the past year. Shares are 26.7% below their last high on Dec. 10, 2024. The company’s stock has a Morningstar Rating of 3 stars and is trading at a 10% premium to its fair value estimate of C$17.50.
Celestica
- Sector: Technology
- Industry: Electronic Components
- Economic Moat: Not Rated
Celestica surged 35.1%, having risen 108.6% from one year ago. Shares are 23.1% below their last high on Feb. 5, 2025. The company’s stock has a quantitative Morningstar Rating of 2 stars.
AtkinsRealis
- Sector: Industrials
- Industry: Engineering & Construction
- Economic Moat: None
AtkinsRealis climbed 31.9%, bringing the stock up 68.9% over the past year. The company’s stock has a Morningstar Rating of 3 stars and is trading at a 10% premium to its fair value estimate of C$82.00.
Finning International
- Sector: Industrials
- Industry: Industrial Distribution
- Economic Moat: Not Rated
Finning International rallied 31.0%, bringing the stock up 27.8% from one year ago. The company’s stock has a quantitative Morningstar Rating of 3 stars.
Cameco
- Sector: Energy
- Industry: Uranium
- Economic Moat: Not Rated
Cameco rose 29.1%, lifting shares 6.4% from one year ago. The company’s stock has a quantitative Morningstar Rating of 3 stars.
Metrics for the Worst-Performing Stocks
Bausch Health Companies
- Sector: Healthcare
- Industry: Drug Manufacturers - Specialty & Generic
- Economic Moat: Not Rated
Bausch Health Companies slid 15.1% in May, leaving the stock down 30.5% for the year. Shares are 54.7% below their last high on Nov. 6, 2024. The company’s stock has a quantitative Morningstar Rating of 3 stars.
Ivanhoe Mines
- Sector: Basic Materials
- Industry: Other Industrial Metals & Mining
- Economic Moat: Not Rated
Ivanhoe Mines slid 13.2%, leaving the stock down 46.0% for the year. Shares are 49.3% below their last high on Sept. 26, 2024. The company’s stock has a quantitative Morningstar Rating of 4 stars.
Alamos Gold
- Sector: Basic Materials
- Industry: Gold
- Economic Moat: Not Rated
Alamos Gold fell 9.8%, but was still up 56.8% over the past year. Shares are 17.3% below their last high on April 16, 2025. The company’s stock has a quantitative Morningstar Rating of 2 stars.
AltaGas
- Sector: Energy
- Industry: Oil & Gas Midstream
- Economic Moat: Not Rated
AltaGas fell 6.0%, shares were still up 29.2% for the year. The company’s stock has a quantitative Morningstar Rating of 3 stars.
Hydro One Networks
- Sector: Utilities
- Industry: Utilities - Regulated Electric
- Economic Moat: None
Hydro One Networks fell 4.7%, but was still up 32.4% from one year ago. The company’s stock has a Morningstar Rating of 1 star and is trading at a 33% premium to its fair value estimate of C$38.00.
Companies that are not formally covered by a Morningstar analyst are statistically matched to analyst-rated companies, allowing our models to calculate a quantitative star rating.
This article was compiled by Frank Lee.
The author or authors do not own shares in any securities mentioned in this article. Find out about Morningstar's editorial policies.