As of 8 a.m. on Wednesday, the company said an approximate 4,300 homes and businesses were still without power in the Laurentians, Outaouais and Lanaudière regions.
Last Friday's 50-centimetre snowfall cut power to about 130,000 customers.
More than 800 Hydro-Québec employees – some on snowmobiles and snowshoes – were working over Christmas Day to help fix power lines that feed individual homes. Work on the primary network was mostly completed Tuesday.
Isabelle Nuckle, a spokeswoman for the public utility, said the work is taking longer than expected because many hydro poles need to be replaced.