The royals must have racked up a fair few airpoints by now, jetting to the antipodes and back every couple of years.
This will be Prince Charles' ninth visit to New Zealand.
During their tiki-tour, the prince and duchess will be visiting Wellington, Dunedin, Nelson, Westport, Ngaruawahia, New Plymouth and Auckland. Their last trip to New Zealand was in 2012, as part of the Queen's Diamond Jubilee Tour.
The royal family must like it here - Prince Harry was here just a few months ago, in May. His trip included a visit to Stewart Island, where he took part in a pub quiz with locals.
And last year, the Duke and Duchess of Cambridge visited with baby Prince George.
The Department of Internal Affairs said it would not be able to provide details of the cost of Prince Charles and the duchess's visit until it was complete.
However, Prince William and the Duchess of Cambridge's 10-day tour in April last year cost the taxpayer about $1 million.
Prince Harry's nine-day visit cost about $425,000.
But is there still enough public interest in these royal visits to justify the cost?
Prime Minister John Key said these regular royal trips to New Zealand were not PR stunts.
They are about staying connected, and it was important New Zealanders got to know their future king, he said.
"One day [Prince Charles] will be king of New Zealand, that's the reality... it's much more challenging for the Queen to travel now, just because big, long distances are harder for her at her age."
Unfortunately for the royal couple, their visit may well be obscured by the return of the Men in Black with their shiny medals and golden cup, arriving home triumphant from the Rugby World Cup.
Their victory parades are guaranteed to attract thousands of people, while the prince and duchess are unlikely to command such crowds.
Mr Key has not ruled out involving the royal couple in one of the All Blacks' victory parades.
"They've got their schedule and whether they can be involved or not is actually a matter for Clarence House.
"I think they have great respect for the achievement of the All Blacks. Whether they can actually alter their schedule? I don't know," he said.
Labour deputy leader Annette King said she doubted that the prince and duchess would want to be part of a parade.
"The idea of them sitting in an open jeep driving up the main street of Auckland in a ticker-tape parade - I don't think they would probably be interested in that."
The royal sceptic
United Future leader Peter Dunne, who is pro-republic, said the golden age of the royals was long over.
"I guess you could say that because they're representative of our head of state from far far away they're worthwhile, but I just think they're a bit of an anachronism and a bit of a look to a bygone time really."
But he was not "churlish" enough to say the royals shouldn't make official visits to New Zealand at all.
"I just don't think we should accord any great status to them.
"I'm actually going to a function with them, I freely concede that, but then I went to a function with the President of Singapore last week.
"I see these things in about the same light. They're goodwill visits from countries we have friendly relationships with, but I don't think they have any special significance beyond that."
He predicted the crowds of New Zealanders that turn out to see the royals will get smaller and smaller as time goes on: "They will just be treated with the same curiosity as any other visiting overseas dignitary is."
He predicts the affection for the royal family won't pass on to the next generation when the Queen "shuffles off this mortal coil".
Mr Dunne believes there is some strategy behind the visits.
"I think there's also a little subtle campaign from the pro-monarchy sector to make sure we bring the attractive royals out here so you can sort of whip up some public sentiment around them."
But staunch monarchist and National backbench MP Paul Foster-Bell scoffs at that.
Mr Foster-Bell's office is decorated with various royal regalia including a framed photograph of the Queen and Prince Philip.
The MP, a former vice-chair of Monarchy New Zealand, wears a tie featuring a pattern of tiny crowns and has matching royal-themed cuff-links.
Mr Foster-Bell said royal visits were advertising opportunities for New Zealand that money could not buy.
Interest had become stronger in recent years, particularly after the visit of Will and Kate, he said.
"I don't put it down to just celebrity value.
"As an institution, the Queen has provided a completely neutral, politically-unbiased referee over our system for now over 60 years and I think people are interested in meeting her successor - her son Prince Charles - who will be our next head of state."
Mr Foster-Bell, who served in the Middle East as a diplomat, said he saw first hand what a useful selling point it was for New Zealand to be part of a monarchy.
"There is prestige, there is a certain mana," he said.
Mr Foster-Bell said New Zealand paid "a small amount, a pittance really" for the occasional royal visit and points out the side-benefits, such as publicity for local companies and charities.
The duchess will be visiting the SPCA in Wellington, for instance.
He may be a committed royalist, but Mr Foster-Bell said he was no "royal fan boy".
"I don't read the magazines that do the gossipy profile pieces on the royal family.
"[But] I've got enormous respect for the Queen... that dedication, the duty and for, I suppose, gratitude for a system that enables New Zealand to be one of the least corrupt and most transparent democracies in the world."
Though Mr Foster-Bell has met the Queen, Prince Harry, Prince Charles and the Duke and Duchess of Cambridge, he does not describe himself as an anglophile.
"I'm quite proud to be a Kiwi and that we have our own system, but I think we need to get over that teen angst where we want to reject and rebel against that system that we originated from."
He said royals are more than just celebrities.
"That's a special thing, particularly in this secular age...to see someone who is on our coins and banknotes and stamps and probably the most recognisible people in the world or a member of her family."
So, do the royals still have much currency here in New Zealand?
Whether Prince Charles and the duchess are considered mere curiosities of a bygone age or legitimate future leaders of this country, it's likely many New Zealanders will still turn out to catch a glimpse of them. Just as long as the royals don't get in the way of a photo with Richie or Dan.
Today, the prince and duchess will be welcomed at Government House in Wellington before laying a wreath at the new Pukeahu National War Memorial.
On Thursday morning, the prince will visit Tawa College and the duchess will visit Te Whaea.
In the afternoon, the couple travel to Dunedin where the duchess will attend a literary reception at Otago University, and then join the prince at an eco-sanctuary.
On Saturday, the couple will travel to Nelson. The prince will visit the Cawthron Institute and the duchess will visit the World of Wearable Art museum.
Prince Charles will also travel to Westport to look in on the Defence Force's training operation Exercise Southern Katipo.
The duchess will return to Wellington and visit the SPCA.
On Sunday, they travel to Waikato and visit the Turangawaewae Marae, the home of the Maori King - with a waka armada on the Waikato River.
On Monday the couple travel to New Plymouth where the prince will visit a dairy farm and the duchess will visit the Len Lye Centre.
They finish their tour in Auckland before flying out to Australia.
More details are available here.