The firm, which sells a products ranging from tools to electronics, does the bulk of its business in Sweden and Norway where stores have stayed open in the pandemic although government restrictions and recommendations have reduced footfall across the retail sector.
But Clas Ohlson has also benefitted from house-bound consumers spending more on their homes.
"Online sales in November have been very strong while we have seen continued fluctuations in customer traffic in our stores where many stores have been negatively affected by current restrictions," it said in a statement.
"The supply chain performed well ahead of our most important sales months of November and December," it said.
The budget retailer has been cutting costs and adapting its offerings and operations to the pandemic, after it closed its loss-making stores in Britain and Germany last year.
It reported a 14% increase in pretax profit for its fiscal second quarter to the end of October from a year earlier, to 132 million crowns on sales of 2.04 billion.
"We have countered major fluctuations in consumer patterns with relevant products and flexible customer interaction," Chief Executive Lotta Lyra said.
(Reporting by Anna Ringstrom; Editing by Johannes Hellstrom and Edmund Blair)