But it hasn't started well.
Royal Caribbean and Norwegian Cruise Line have both cancelled some voyages this week.
That as resurgent virus cases hit passengers and sap demand.
Royal Caribbean cancelled one sailing after nine guests were identified as close contacts of a person who tested positive.
The passengers subsequently all tested negative, but the ship returned to port to test everyone on board.
Norwegian has also cancelled sailings against the backdrop of record case numbers in the U.S.
The cruise line, which requires everyone on board to be vaccinated, also had to cut short one trip from Miami due to heath concerns.
It says people booked on affected sailings will receive full refunds and bonus credits.
Last week the U.S. Centers for Disease Control recommended against going on cruises.
It's launched investigations into onboard cases on more than 90 ships.
However, Carnival Corp, the world's largest cruise operator, says it is yet to cancel any trips.
