Econet Wireless confirmed in a Twitter message to subscribers that WhatsApp connectivity had been restored just after midday.
"Please be advised that WhatsApp is now back up. We sincerely apologise for any inconveniences caused," the customer care department tweeted.
WhatsApp has also been restored on other networks such as Telecel and NetOne, Fin24 understands.
Harare - Instant messaging app WhatsApp experienced downtime on mobile networks in Zimbabwe on Wednesday as protest action started taking root.
Zimbabweans woke up to no WhatsApp connectivity through their mobile phones on Wednesday, a rare occurrence in the country over the past few years.
The unavailability of WhatsApp coincided with nationwide protests which has fueled suspicion that government asked telcos to cut WhatsApp connectivity.
Econet Wireless, the biggest of Zimbabwe's three mobile operators, confirmed around midday on Wednesday that WhatsApp was down on its network.
Econet, though, did not disclose the reason for the downtime.
"Econet would like to confirm that WhatsApp is currently down. We will notify you once it is working again," Econet's customer care department said in numerous Twitter responses to subscribers.
There was no clarification from NetOne and Telecel Zimbabwe, the other mobile operators in Zimbabwe.
However, other subscribers on these networks also complained that they were struggling to access WhatsApp on the networks.
Other social networks
Although WhatsApp has been down in Zimbabwe since early Wednesday, Facebook and Twitter platforms were working well.
Zimbabweans took to Twitter to express outrage over the termination of WhatsApp and to share pictures of the strike online.
The protests have been organised to raise public outrage over government corruption, delayed salaries for civil servants and police roadblocks.
Civil servants have also downed tools, prompting school children to stay away from school and public hospitals to run with limited staff.
This comes on the back of protests in Beitbridge at the weekend over import restrictions.
Harare, the capital, was also rocked by protests in the public transport sector with workers in the sector blocking transport movement over police harassment.
Pictures of the protests and communications urging Zimbabweans to "shut down" the country have been spread over WhatsApp.
However, government officials still claim it has been business as usual despite most people staying away.
"If there's a stay away as you claim then stay away from WhatsApp. What's gud (sic) for the goose is gud (sic) for the gander!," tweeted outspoken higher education minister, Jonathan Moyo on Wednesday morning.