The power outages would be reduced to "Stage 3" on Saturday and to "Stage 2" on Sunday morning, Eskom said in a short statement.
A further update would be provided on Sunday, it said.
This week, Eskom has been implementing "Stage 4" outages, reducing supplies on the national grid by up to 4,000 megawatts (MW). Under Stages 3 and 2, the reductions are 3,000 and 2,000 MW, respectively.
The past week has seen some of the worst power cuts on record in Africa's most industrialized nation, at least six hours a day for most households and often as much as 10 hours.
ESKOM frequently blames its blackouts on broken equipment. The state-owned utility was reportedly looted of its funds in the "State Capture" scheme purportedly done by associates of former President Jacob Zuma.
