Windsor's unemployment rate climbed 0.6 percentage points to 11.1 per cent last month as the city lost 3,700 jobs.
The Labour Participation Rate also slipped below the 50 per cent mark to 49.8 per cent.
Statistics Canada released its Labour Market Survey on Friday showing gains in the jobless rate locally, provincially, and nationally.
Across the country, the jobless rate inched upwards for the first time since April. It was 8.6 per cent, a slight increase from November's 8.5 per cent.
The national economy lost 63,000 net jobs. Accommodation and food services took a hit for the third consecutive month and December was the second month in a row employment fell in information, culture, and recreation.
The number of self-employed also dropped by 62,000, but employment in the public and private sectors held steady.
There are still 1.1-million Canadians who either lost their jobs or had their hours reduced because of the COVID-19 pandemic.
About one in four Canadians also worked from home last month, 28.6 per cent in December.
In Ontario, where lockdowns took effect in Toronto and the Peel Region on November 23 and in Windsor-Essex and the York Region on December 11, the unemployment rate climbed 0.4 percentage points to 9.5 per cent. However, there was little change to the number of people working overall. The agency blamed the increase on more people looking for jobs.
The survey was taken between December 6 and December 12, 2020.