The first since 2005, the Lions Tour kicks off on June 3, continuing for just over a month.
The previous tour brought about 20,000 overseas visitors and a more than $120 million cash injection to the New Zealand economy - something the country is hoping to top.
Armitage said Ateed was expecting about 20,500 overseas visitors for the event, with the additional 165,000 visitor nights expected to bring in about $27m to Auckland's economy alone.
All Blacks Hospitality chief executive Warren Barclay earlier told the Herald his firm had noted strong demand for accommodation in Wellington and Auckland in particular over the month of the tour, saying while there would be a strain on accommodation at test venues, other regions outside the main centre would likely do well out of the event.
Barclay said home rental services such as Airbnb could fill the accommodation shortfall.
"It will be interesting to see how it goes," he said. "We worked a lot with a couple of savvy operators of luxury rentals in 2011 [for the Rugby World Cup] and they did pretty well out of it."
According to Armitage, although accommodation was always going to be a pressure point, the success of the World Masters Games last week proved the country was capable of hosting such large-scale events.
"The [Games] were a great example of us being able to cater to the demands of the 16,000 international visitors that came in to take part in the Games," Armitage said.
"This is a bit higher but we're very confident there's enough accommodation and a range of activities and attractions for people to get involved in when they're not enjoying the rugby."
Accommodation and tourism were not the only sectors likely to profit from the tour, with visitors likely to take advantage of New Zealand's hospitality and retail scene too.
Advocacy and policy manager at Hospitality New Zealand Dylan Firth said international rugby fans - two-thirds of whom were expected to come from Britain and Ireland - were likely to spend more money, with their currency going further in New Zealand, and having travelled so far to attend the games.
"It's one of those things, people like to go out for a meal and a drink and then at the stadium they'll have a couple of beers too," Firth said.
"For the British crowd, they've come across the other side of the world so they may as well make the most of it."
According to Firth, the dollar value was just one factor. The tour was also expected to offer employment opportunities for 2500 full-time equivalent employees.
The regions would also do well, he said, with visitors expected to take day trips to areas such as the Coromandel or Wairarapa in between games.
"Really most sectors are going to benefit from this - airlines, hospitality, retail, accommodation, tourism," Firth said. "It's a short period of time in which a lot of money is injected into the economy."
Retail Association public affairs general manager Greg Harford said the retail community was preparing for the event, with the tour expected to be good news for the sector.