People from Chicago to the Canadian Maritime provinces and from the southern tip of Hudson Bay to Washington, DC, reported feeling the jolt, which struck at 1:41 p.m. Eastern Daylight Time.
From an epicenter in western Quebec, about 33 miles north-northeast of Ottawa, the quake caused thousands of people across a wide region to rush outdoors as the ground shook for about 30 seconds.
Several buildings in Toronto and the Ottawa region were evacuated.
Despite the vast geographical area affected by the quake, there were no reports of signficiant damage or any injuries.
The two largest quakes that have struck western Quebec in the past occurred in 1935 at magnitude of 6.1 and in 1732 at a magnitude of 6.2, according to the Canadian Geological Survey.