The owner of the ill-fated Phoenix dive boat on Friday pledged full compensation for passengers of the boat.
Woralak Rirkchaiyakarn said her company would ensure that tourists are well cared for and shoulder their medical bills.
Woralak said her company would also make insurance claims to compensate the injured and dead.
The Phoenix dive boat ran into trouble on Thursday afternoon, when it was hammered by five-metre-high waves that had been whipped up by a storm.
The boat was returning to Phuket from the popular snorkelling spot of Koh Racha carrying 105 passengers, the majority of them Chinese tourists.
The body of a Chinese tourist has been found, but 56 people were still missing on Friday morning.
Woralak said her company would also assist the families of tourists to transport the bodies of their loved ones back home for religious services.