Reflection departed from Fort Lauderdale on Saturday (6 November) on a seven-night voyage with stops in the Bahamas, Mexico, Belize and Honduras.
A day later Constellation left its new homeport of Tampa Bay for a sailing with stops in Belize and Cozumel, Mexico.
Each ship will now sail the Eastern and Western Caribbean for six months before embarking on European itineraries with stops in Italy, Spain, Greece, and Croatia.
With the return of the two vessels, ten of Celebrity’s 14 ships have now returned to service in 2021.
Celebrity Cruises’ president and chief executive Lisa Lutoff-Perlo said the past year has been "one of remarkable change".
"But we can definitely say the announcement of the return of these two marvellous ships is a change in the right direction as we invite our guests back on board," she added.
"The experiences our guests will enjoy aboard these beautiful new-luxury ships will provide the healing power of travel that we have all been seeking."
