New Zealanders felt safe travelling domestically and were spending some of the $7b to $9b they spent on overseas trips on holidays here.
A year since switching its decades-old focus on international visitors to the domestic market, he said the organisation had developed a better understanding of Kiwi travellers.
"They are the perfect visitor for us - they travel all year round."
There were three main drivers: Kiwis like stunning scenery and landscapes, like to unwind and relax and want to try new things - active relaxing.
Spreitzer said TNZ's "Try something new New Zealand" had encouraged them to travel to new spots and try new activities.
More than half of New Zealanders have done a new tourism activity or visited a new place since May last year and TNZ has calculated that its domestic campaigns had reached three quarters of the population.
Kiwis were more price-sensitive than overseas visitors but once they knew what they were getting they were usually happy to pay for experiences.
"Once a New Zealander understands what it is that they're buying they're prepared to pay for it," he said.
"There are some tourism experiences they might do overseas but not in New Zealand but a year in they have spent a lot more money and 84 per cent say they love what they're doing in New Zealand."
Active relaxing included cycling and Spreitzer said the 22 Great Trail Rides had experienced a busy summer. He said while some tourist spots had boomed others with a heavier reliance on overseas visitors had continued to suffer badly.
The Tourism NZ figures, from Ministry of Business, Innovation and Employment data, are backed up by Bachcare numbers which show domestic bookings in April were 113 per cent up on the same period in 2019.
Year to date bookings are up 38 per cent versus the same period in 2019 - pre-pandemic.
Spreitzer said one benefit of more happy Kiwi domestic tourists would be their role as "unofficial ambassadors" for the country when they could travel overseas again.
