The one-hour show, titled River Deep; Mountain High, was dedicated entirely to New Zealand and followed Hobbit-star James as he journeyed north to south, taking in some of the country's most unique landscapes and tourism experiences along the way.
It was broadcast to an estimated four million viewers in the UK on ITV at 2:00pm on Christmas day, before screening a second time an hour later on ITV+1.
The Irish star first came to New Zealand whilst filming The Hobbit and returned earlier this year to film his documentary with Alaska TV.
The production was supported by Tourism New Zealand's International Media Programme, which coordinated James' itinerary with Regional Tourism Organisations and provided on-the-ground support for the production.
Motueka operator U-Fly Extreme, which featured in the documentary, says they have already had several inquiries, three bookings and two flights from UK tourists who had seen it.
Tourism New Zealand's Director of Trade, PR and Major Events Justin Watson says the return for supporting such high-profile international broadcast opportunities is achieving endorsement of New Zealand as a visitor destination from popular and influential celebrities.
"James Nesbitt is hugely popular at the moment and with the current hype around The Hobbit: The Desolation of Smaug, having him film this travel programme here, was a huge coup for us.
"Endorsement of this nature and through this medium will reach millions of viewers and is bound to stimulate the desire for a New Zealand holiday in all those British folk experiencing a wintery Christmas day.
"We know that the endorsement of others remains one of the most influential factors in helping people make travel decisions and when endorsement comes from popular and appealing celebrities, the impact is even stronger."
In a press release from ITV promoting the show, James says: "It's a country of contrasts, from its extraordinary, untamed landscapes to its modern cosmopolitan cities, from tribal warrior traditions to the world's third most peaceful nation. And yet despite being so far away it feels surprisingly familiar."
The release goes on to say: "Travelling over 1,000 miles from the tip of the North Island down to the South, James visits areas of stunning natural beauty and learns about the history and traditions of this distant country.
"Along the way he immerses himself in culture and meets Kiwi legends; All Blacks star Jonah Lomu, film director Peter Jackson and actor Sam Neill." The actor's travel took him from Auckland to Wanaka, visiting Waitomo; Rotorua; Wellington; Nelson; Christchurch and Central Otago along the way.
ITV is the largest commercial television network in the UK, with ITV1 being the largest commercial channel in the UK, consistently attracting the largest UK audiences of any UK commercial broadcaster.