Statistics Canada says the economy lost 213,000 jobs in January as employment fell to the lowest level since August last year, wiping out the gains made in the fall.
The unemployment rate rose 0.6 percentage points to 9.4 per cent, the highest rate since August.
Financial data firm Refinitiv says the average economist estimate was for a loss of 47,500 jobs in January and an unemployment rate of 8.9 per cent.
The losses were almost entirely concentrated in Ontario and Quebec, and mostly in the retail sector as lockdowns and restrictions closed many businesses.
Employment declines were heavy in the services sector and part-time work fuelling the largest monthly decline since April when some two million jobs were lost.
Statistics Canada says the losses in January now put the country at 858,300 jobs, or 4.5 per cent, short of employment levels from last February just before the first wave of the COVID-19 pandemic.