Te Mana o Ngati Rangitihi chairman Leith Comer said ownership of Waimangu would bring important strategic and commercial benefits for the iwi.
"This is a significant milestone for both Ngati Rangitihi and Tuhourangi and provides a strong platform to enable the continued success and growth of our people," he said.
"The purchase also provides an opportunity to build on the work undertaken by Waimangu kaitiaki, the late Harvey James," Mr Comer said.
Mr James, who died in February, was an award-winning environmental tourism leader and recipient of a Rotorua Lakes Council community leadership award for his work with the natural environment.
His work will be celebrated with a maumahara (remembrance) at Waimangu.
"We feel a keen sense of responsibility to build on Harvey's vision and we're looking forward to working with his wife Trudi through this transition," Mr Comer said.
Mrs James said her husband would have been thrilled to transfer his life's work and passion to a partnership of Ngati Rangitihi and Tuhourangi.
"We are very confident we have chosen the perfect partners to continue Harvey's vision of leading New Zealand in sustainable environmental tourism and his commitment to preserve the valley for future generations to study and enjoy," she said.
Tuhourangi Tribal Authority chairman Alan Skipwith said today's confirmation of the purchase also marked the beginning of a new chapter in the relationship between Ngati Rangitihi and Tuhourangi.
"Tuhourangi and Ngati Rangitihi have strong whakapapa hononga (connections) and an integrated mana whenua.
"We've realised that it's time to work together for the benefit of our people and to ensure that an important element of the region's tourism landscape stays in iwi hands.
"Let's not forget that it was iwi who led New Zealand's first tourism venture when hosting visitors at the Pink and White Terraces.
"More broadly, this purchase is about helping both our iwi reconnect with their tribal lands," Mr Skipwith said.
The new ownership structure will involve a joint partnership between the two hapu, which will be supported by Te Puia.
The new company, Waimangu Volcanic Valley (2017) Limited, will have a board consisting of two representatives from Te Mana o Ngati Rangitihi, one from Te Puia and one from the Tuhourangi Tribal Authority - with a revolving chairmanship starting with Mr Skipwith.
Rotorua Lakes Council Te Tatou o Te Arawa chairman Te Taru White said the sale was another sign the "taniwha of the Maori economy was well and truly waking up".
"It's great to see that resource go back into iwi hands and it shows what's happening in the iwi space is a desire to hone their economic assets - especially ones that have been in their ownership in the past.
"It would also add to the cultural tourism offering at the place that once held the eighth Wonder of the World - the Pink and White Terraces," he said.
