The Canadian Securities Exchange began operations in 2003 to provide a modern and efficient alternative for companies looking to access the Canadian public capital markets. The operating company, CNSX Markets Inc., was recognized by the Ontario Securities Commission as a stock exchange in 2004.

Designed to meet the needs of emerging companies and their investors, CSE has grown continuously and now lists more than 600 equities and convertible securities.

In September 2007, the exchange launched the first continuous auction market to trade securities listed on other Canadian stock exchanges. The new facility introduced a high capacity, low latency trading environment combined with an attractive fee structure that enabled the Canadian trading community to use advanced trading technologies to their full advantage, while delivering cost savings enhancing the competitiveness of the Canadian markets.

Following the completion of "Project One" on December 2, 2013 CSE listed symbols and stocks listed on other Canadian exchanges are now being traded on a single system at the CSE.