Younger and vulnerable workers felt the decline the most but women among core-age workers were hit hard.
Private sector jobs felt the brunt of the decline with the largest job losses seen in the accommodation and food services industry.
"It is expected that the sudden employment decline observed in March will have a significant effect on the performance of the Canadian economy over the coming months," StatsCan said.
"The employment decline in March was larger than in any of three significant recessions experienced since 1980
B.C. Finance Minister Carole James said the effects of the COVID-19 pandemic are apparent in the numbers.
"We know today's numbers reflect the initial impacts of the pandemic, and a fuller picture will become clear in next month's report," James said. "This is a stressful time for all British Columbians, but I want people and businesses to know our government is doing everything it can to support them-and together we will get through this."
The federal agency called it a "shock," saying further measures are needed to quantify COVID-19's impacts.
"This includes measures of Canadians who kept their job but worked reduced hours, and the number of people who did not look for work because of ongoing business closures, StatsCan said.
Provincially, employment fell in all provinces, with Ontario (down 403,000 or -5.3 per cent), Quebec (down 264,000 or -6.0 per cent), British Columbia (down132,000 or -5.2 per cent) and Alberta (down 117,000 or -5.0 per cent) reporting the largest declines.
The unemployment rate increased 2.2 points to 7.8 per cent in March, the largest one-month increase on record, a level last observed in October 2010.
From February to March, the number of unemployed increased by 413,000 (up 36.4 per cent), the largest monthly change since comparable data became available in 1976.
That rate increased in all provinces except Newfoundland and Labrador and Prince Edward Island. The largest increases were in Quebec (up 3.6 percentage points to 8.1 per cent), British Columbia (up 2.2 percentage points to 7.2 per cent) and Ontario (up 2.1 percentage points to 7.6 per cent).
Almost all of the unemployment increase was due to temporary layoffs, meaning that workers expected to return to their job within six months, StatsCan said.
StatsCan figures indicate employment decreased more sharply in March among employees in the private sector (-830,200 or -6.7 per cent) than in the public sector (down 144,600 or -3.7 per cent).
The number of self-employed workers decreased relatively little in March (down 1.2 per cent or -35,900), and was virtually unchanged compared with 12 months earlier.
"At the onset of a sudden labour market shock, self-employed workers are likely to continue to report an attachment to their business, even as business conditions deteriorate," StatsCan said.
Employment for youth aged 15 to 24 decreased by 392,500 (down 15.4 per cent) in March, the fastest rate of decline across the three main age groups, a decrease was almost entirely in part-time work.
About 20 per cent of employed youth lost all or the majority of their usual hours.
The core working age group is 25 to5 4.
Women in that group saw a decline twice that of men, down 298,500. Nearly half of the decrease among women was from part-time employment, down 144,100 or-14.0 per cent.
StatsCan said workers in less secure, lower-quality jobs, were more likely to experience employment losses in March. The number of those in temporary jobs decreased by 14.5 per cent (down 274,900) compared with a decline of 5.3 per cent (down 749,500) among employees with permanent jobs.
Decreases were seen for all temporary work, led by those in casual employment, down 23.5 per cent or-136,000 jobs.
James said B.C.'s COVID-19 Action Plan builds on that of Ottawa to support people and businesses worried about paying bills.
"This includes the $1,000 B.C. Emergency Benefit for Workers, relief for renters, a three-month credit for affected BC Hydro customers, as well deferment of taxes for businesses, cutting the school property tax by 50 per cent and additional relief for people and businesses," James said.
