Carnival Cruise Line said the Carnival Sunshine will return to sailing from Charleston, S.C., on Jan. 13, and the Carnival Liberty from Port Canaveral, Fla., on Feb. 11.
With the return of the two ships, Carnival will have 90% of its U.S. capacity back in operation.
Cruises on Carnival's three remaining U.S.-based ships -- Carnival Ecstasy from Jacksonville, Carnival Paradise from Tampa and Carnival Sensation from Mobile -- have been canceled through February.
"Our restart plan continues to excel across all metrics, and we are looking forward to completing the restart of the fleet in the new year," said Carnival Cruise Line president Christine Duffy.
In Australia, sailings of the Carnival Splendor from Sydney are canceled through Feb. 7, and Carnival Spirit cruises from Brisbane are canceled through Feb. 20.
Carnival will continue to operate vaccinated cruises under its current protocols.
Duffy said that Carnival is "optimistic that vaccines will be approved for children between the ages of 5 and 11 before the end of the year, and we look forward to welcoming more families back on board."