All 1,112 grid stations were back online, a senior government official told Reuters, adding that electricity would be fully restored across the country once power generation units were back up. The official declined to be named as they were not authorised to speak to the media.
The outage, which began on Monday morning during the peak winter season, is the second major grid failure to hit the nation of 220 million people since October, though there are partial blackouts almost daily.
Residents in major cities said they now had electricity, but some areas of the country were still without power.
Analysts and officials blame the power problems on an ageing electricity network, which like much of the national infrastructure, desperately needs an upgrade that the government says it can ill afford.
The International Monetary Fund has bailed out Pakistan five times in the last two decades. Its latest bailout tranche, however, is stuck due to differences with the government over a programme review that should have been completed in November.
Pakistan has enough installed power capacity to meet demand, but it lacks resources to run its oil-and-gas powered plants. The sector is so heavily in debt that it cannot afford to invest in infrastructure and power lines. China has invested in its power sector as part of a $60 billion infrastructure scheme that feeds into Beijing's "Belt and Road" initiative.
(Reporting by Asif Shahazad in Islamabad, Gibran Naiyyar Peshimam and Ariba Shahid in Karachi, additional reporting by Jibran Ahmad in Peshawar; writing by Shilpa Jamkhandikar and Miral Fahmy; editing by Simon Cameron-Moore)
By Gibran Naiyyar Peshimam and Asif Shahzad