The auction is due to take place on Wednesday in Bangkok.
The three qualified bidders are Thai Transmission Industry (TTI), a Thai telecom system integrator; Supreme Distribution, a local computer maker; and Haier Group, a Chinese consumer electronics appliance maker, said a highly placed source on the auction project.
They passed the technical round, including drop tests to supply 800,000 tablets to Prathom 1 students in Zones 1 and 2 in the second phase after two other bidders were dropped.
Zone 1 covers central Thailand and the southern provinces, while Zone 2 covers the North and Northeast.
Both TTI and Haier earlier failed in the first round of tablet auctions for the second phase, while Supreme Distribution won a bid to supply tablets in Zone 3.
The second-round auction has to held after China's Shenzhen Yitoa Intelligent Control Co, which won the first-round auction, terminated two purchase contracts last month with the Thai government to supply 800,000 tablets after the company failed to deliver all tablets within 90 days of the contract signing last September. The deal was worth 1.63 billion baht.
The government seized the 120-million-baht bank guarantee deposit from Yitoa for delivery failure. The Office of the Attorney General is also on the brink of suing Yitoa for an additional fine of 108 million baht for delivery failure. The government is also seeking legal action against Yitoa to cover extra costs if the new tablet prices from the second-round auction increase.
The caretaker education minister had said a tablet e-auction for the third phase would be held by April 15.