A week of persistent heavy rainfall in the province has caused an increased number of unplanned breakdowns at the cash-strapped power utility.
It was said that stage 6 had been implemented following a "technical problem" at the Medupi power plant which had impacted on additional generating supply.
"Load shedding is required all day today to cater for further trips and to create capacity to replenish water reserves for our pumped storage schemes".
"We remind and assure customers that loadshedding at stage 6 is no cause for alarm as the system is being effectively controlled", Eskom said. However, since load shedding is rotational, people were caught off guard because the current gazetted schedule only goes up to stage 5. "We continue to utilise diesel and water resources at our open cycle gas turbines and pumped storage schemes respectively, to supplement capacity", they said in a statement.
During Stage 4, 4000MW is rotationally loadshed nationally at a given period. The utility downgraded the status to Stage 4 as of 10 p.m.
Residents are encouraged to help Eskom by using electricity sparingly.
"We sincerely apologise for the inconvenience during this hard period", said Eskom.
South African Twitter users - known for being facetious - have once again responded with all manner of tweets, GIFS, memes and videos to the news, with the most pertinent question being: "What is stage 6 load shedding?" while others speculated on what the other stages unofficially meant.
You can also check your loadshedding schedule by downloading the Eskom Push app.