Chris and Brian Plaskett, of Seaford, East Sussex, said they enjoyed celebrations on board the 1824 berth Volendam as it sailed along the east coast of the South Island, but could not adjust to a far from white Christmas.
"Christmas lunch was very weird for us.
"We are used to cold weather," Mrs Plaskett said.
A highlight was seeing snow on mountains near the coast, possibly near Kaikoura.
Mrs Plaskett said while the turkey dinner was well prepared it was "not quite a traditional English midday meal" and she missed mince pies, Christmas pudding and stuffing.
"But there was no washing up either," Mr Plaskett said.
Passengers were entertained by European and Filipino staff who sang in two choirs.
The couple were looking forward to seeing Fiordland before heading to Sydney for New Year's Eve celebrations.
Millennium passengers Sally Corbett and Ashley Dean, both from the Sydney suburb of Kirribilli, said passengers celebrated Christmas a day early, and in true European style enjoyed a traditional buffet meal on Christmas Eve.
Ms Corbett said about 1200 of the passengers were from the United States, 700 from Australia, with the rest being New Zealanders.
They both enjoyed the cruise ship experience which was a "hassle free" way to travel, but hoped the weather would be fine as the ship crossed the Tasman this week.
Bead Shop owner John Menzies said most shoppers in his Octagon store on Saturday were from the two passenger ships, and retailers in the CBD would be glad for the influx of customers.
"Most of them are from the ships today, and we are always glad when they are in town at this time of year.
"They mostly go for paua and jade items - anything with a New Zealand slant," Mr Menzies said.
The 60,906gt, 237m-long Volendam has 720 cabins.
It was scheduled to make 10 visits to Otago this season.
Celebrity Cruise Lines launched the 1950 passenger Millennium in July 2000.
At 91,000gt, the ship was the largest at the time built in France.
Both ships left Dunedin for Milford Sound on Saturday night.
