According to a power ministry notification, the increase will apply to consumers of all power companies, including the Karachi Electric Supply Company, except the lifeline consumers using less than 50 units per month.
The decision will generate about Rs1 billion a month and increases will follow in coming months.
A senior ministry official said the special surcharge had been imposed to cover a legal problem arising out of the National Electric Power Regulatory Authority (Nepra) Act. As a result, the tariff will go up by an average 17 paisa, ranging between nine and 27 paisa per unit.
The tariff for the first 100 units has been raised by nine paisa per unit to Rs4.54 and for units between 101 and 300 by 13 paisa to Rs6.87.
The third slab of domestic consumers using 301 to 700 units will pay 21 paisa per unit higher to Rs10.78 and those using more than 700 units will be charged at 13.56 per unit, an increase of 27 paisa.
The tariff for bulk domestic consumers in housing colonies has been increased by 17 to 23 paisa per unit depending on categories.