The National Energy Regulator is sticking with its decision to allow Eskom to increase tariffs by 18.65 percent.
The increase will come into effect from next month for standard customers.
Municipalities will be paying 18.49 percent more for electricity, but only from July.
The announcement comes after President Cyril Ramaphosa had asked Eskom to reconsider the tariff hike.
There was an outcry from consumers when the increased amount was first approved earlier in the year.