The line has removed all pre-cruise testing for departures from October, but said it will "continue to follow local guidance accordingly".
However, under Greek law for cruise ships, all customers must be tested by a medical professional at the port terminal before boarding the ship.
Therefore, all guests aged two and over sailing from Corfu will need to purchase and complete an antigen test the day before boarding the ship until informed otherwise.
Chris Hackney, managing director of cruise for Tui UK and Ireland, said: "As always, our customers are our number-one priority, and the relaxation of these rules means our guests can enjoy a simpler process pre-travel, without having to spend any additional costs."
