The ship was handed over at the yard in Emden, Germany, by shipbuilder Meyer Werft. Spirit of Adventure had been scheduled to offer cruises this summer, but will now not undertake an inaugural voyage until next February, when it will head to the Canary Islands.
The vessel joins sister ship Spirit of Discovery, which became part of the Saga Cruise fleet in July 2019.
Spirit of Adventure has 554 all-balcony cabins and can accommodate 999 passengers.
Saga Cruises managing director Nigel Blanks said: “This is a really exciting day for us as Spirit of Adventure officially becomes part of the Saga Cruises family.