In 2018, Carnival Corporation announced that Star Princess would be transferred to P&O Cruises Australia to accommodate P&O's expansion plans in Oceania; however, amid the COVID-19 pandemic and its subsequent impact on tourism, Carnival Corporation accelerated the transfer of the vessel and Star Princess joined P&O's fleet in 2020, one year earlier than planned.

[1] The two 109,000 GT Grand-class ships were scheduled to be delivered in 2001, and slotted to sail in the Caribbean from Port Everglades year-round.

[10] Star Princess would become the first then-dubbed "mega-ship" ever to be homeported in Los Angeles and also cruise from the West Coast on a full-time basis.

[4][11] At the time of her delivery to Princess Cruises, Star Princess was too large to make a Panama Canal transit, so to arrive in Los Angeles, she embarked on an eastward voyage from Italy, taking her through the Mediterranean, the Suez Canal, the Indian Ocean, and a 26-day inaugural voyage across the Pacific Ocean.

[14][15] For winter 2019–2020, she was homeported in Los Angeles and sailed itineraries to the Mexican Riviera, Sea of Cortez, and Hawaii.

[26] In December 2019, P&O announced that Pacific Encounter would homeport in Brisbane beginning in November 2021 and cruise to different destinations in Oceania, including the Queensland coast and Melanesia islands.

[2] On 23 March 2006, at approximately 3:00 am, while en route from Grand Cayman to Montego Bay, Jamaica, a fire broke out in the passenger compartments in the midship section on the port side of the ship.

[32] Lifeboats were lowered but proved to be unnecessary, as the fire was contained and doused, and the ship headed into Montego Bay under her own power.

While a smoldering discarded cigarette probably did cause the flames, the following items were also at fault for allowing the fire to spread as quickly as it did: The cruise was terminated in Montego Bay and passengers were evacuated to hotels in Jamaica and subsequently flew home.

With 79 cabins destroyed and a further 204 damaged, the ship was moved to the Bahamas where she was prepared for a transatlantic crossing to the Lloyd Werft shipyard in Bremerhaven, Germany, for repairs.

[37][38] Princess implemented new measures that aim to prevent a disaster of similar proportion, which include enhanced procedures for handling fires and clear communication during emergencies.

[38] Passengers reported that the only noticeable differences were a strong smell of new carpeting, the addition of sprinklers to all balconies and the replacement of plastic furniture with non-combustible alternatives.

[39] On 10 March 2012, en route in the Pacific Ocean off the coast of South America, three passengers from Star Princess spotted a small boat drifting with waving seamen, apparently in distress, and notified the crew.

[40] On 19 March, the Ecuadorian coast guard rescued the Panamanian fishing boat Fifty Cent with one survivor on board.

As supporting evidence, the cruise line made public the results of a drift analysis and a photographic investigation they had commissioned.