[QuickLinks -- Click here to rapidly navigate through this document Unless otherwise indicated or unless the context otherwise requires, "we," "us," "our company," "our" or "Canadian Solar" refers to Canadian Solar Inc., a Canadian company, its predecessor entities and its subsidiaries . "China" or "PRC" refers to the People's Republic of China, excluding Taiwan and the special administrative regions of] [Use these links to rapidly review the document CANADIAN SOLAR INC. Unaudited Condensed Consolidated Balance Sheets as of December 31, 2014 and September 30, 2015 F-2 Unaudited Condensed Consolidated Statements of Operations for the Nine Months Ended September 30, 2014 and 2015 F-3 Unaudited Condensed Consolidated Statements of Comprehensive Income for the Nine Months Ended September 30, 2014 and 2015] [FORM 6-K CANADIAN SOLAR INC. 545 Speedvale Avenue West ý o Form 20-F o o CANADIAN SOLAR INC. Form 6-K TABLE OF CONTENTS Incorporation by Reference]

[Canadian Solar Subsidiary Recurrent Energy Secures Debt Financing for 200 MW Garland Solar Power Project GUELPH, Ontario, Canada, December 18 , 2015 With NORD/LB as the Coordinating Lead Arranger, five banks, including CIT, KeyBanc, Rabobank, and Santander will provide project-level construction debt, LC facilities and a back-leveraged term facility, totaling approximately $480 million. “With the closing of the Garland solar] [Canadian Solar Subsidiary Recurrent Energy Partners in 200 MW Garland Solar Power Project GUELPH, Ontario, Canada, December 18, 2015 Under the terms of the agreement, Southern Power will acquire 51% of the equity in the solar generation project. Canadian Solar will retain 49% ownership and contribute its share of the investment required to complete the construction of the project, which] [FORM 6-K CANADIAN SOLAR INC. 545 Speedvale Avenue West Form 20-F x o o o CANADIAN SOLAR INC. Form 6-K TABLE OF CONTENTS 3 4]

[Canadian Solar Secures Additional $80 million Term Loan with Credit Suisse GUELPH, Ontario, Canada, December 15 “We are pleased with the positive outcome of this transaction and we appreciate the confidence of the lenders in our business,” said Dr. Shawn Qu, Chairman and Chief Executive Officer of Canadian Solar. “The buildout of our high value solar project pipeline in the] [FORM 6-K CANADIAN SOLAR INC. 545 Speedvale Avenue West Form 20-F x o o o CANADIAN SOLAR INC. Form 6-K TABLE OF CONTENTS 3 4]

[Canadian Solar Subsidiary Recurrent Energy Partners in 157 MW Texas Solar Project GUELPH, Ontario, Canada, November 30, 2015 Under the terms of the agreement, Southern Power will acquire 51% of the equity in the solar generation project. Canadian Solar will retain 49% ownership and contribute its share of the investment required to complete the construction of the project, which the] [Canadian Solar Subsidiary Recurrent Energy Secures Debt Financing for 157 MW Texas Solar Project GUELPH, Ontario, Canada, November 30, 2015 With KeyBank as the Coordinating Lead Arranger, five banks, including Rabobank, Santander, NORD/LB, and CIT will provide project-level construction debt, LC facilities and a back-leveraged term facility, totaling approximately $275 million. “This top tier group of financiers’ attraction to the] [FORM 6-K CANADIAN SOLAR INC. 545 Speedvale Avenue West Form 20-F x o o o CANADIAN SOLAR INC. Form 6-K TABLE OF CONTENTS 3 4]

[Canadian Solar Subsidiary Recurrent Energy Closes Financing for 100 Megawatt Astoria Solar Power Project GUELPH, Ontario, Canada, November 19 , 2015 Recurrent Energy will be the managing member of the Astoria solar power project and plans to own and operate the facility. Santander Bank, N.A. (Santander) was the coordinating lead arranger of a five member bank club including, NORD/LB, Rabobank,] [FORM 6-K CANADIAN SOLAR INC. 545 Speedvale Avenue West Form 20-F x o o o CANADIAN SOLAR INC. Form 6-K TABLE OF CONTENTS]