The city of Tshwane supplies water and electricity to neighbouring regions, government departments, businesses and embassies, but it says it's owed R6.6bn ($583m; £368m) in unpaid bills.
Now the city says it will start cutting off customers if the debts aren't settled, and the Times Live website reports it could happen within 48 hours. Pretoria's schools have already felt the brunt of the plans, with 38 having their electricity cut so far. "The schools will remain disconnected until all arrears have been settled," Tshwane city manager Jason Ngubeni says. "It has been a painful process for us to embark on this exercise but we could not allow ourselves to fall behind in terms of provision of services."
Three neighbouring municipalities, home to nearly one million people, are also apparently in arrears and at risk of losing services.
But the news may come as a shock to one of the affected regions, Thembisile Hani, where a spokeswoman tells Business Day Live they've paid their bills. "We make sure that we are on top of our water budget... the information from our supply chain management says we are not owing them any money," she says.