The match is part of a triple header including games between the New Zealand Defence Services and Police and the World Champion Black Ferns and a Barbarians team.
As previously reported by RNZ Pacific, the repechage qualifier will be staged at the Trusts Arena in Waitakere, with the winner to advance to the final Rugby World Cup repechage tournament.
The match was originally meant to take place in Apia in April but was postponed due to Covid-19.
Oceania Rugby General Manager Bruce Cook said they're delighted to finally have the details confirmed.
"We are grateful to the New Zealand Rugby Union in hosting the much-anticipated qualification match for Tonga and Samoa, and we are looking forward to a great game," he said.
"It should be an exciting feature as both teams are very determined to make it through the next round of Rugby World Cup qualification."
Tonga defeated Papua New Guinea in March to secure their showdown against the Manusina, who last featured at a World Cup in 2014.
Oceania Rugby Competitions Manager Wayne Schuster said that the organisation is looking forward to work with New Zealand rugby in facilitating the key match which has been greatly anticipated from both unions.
A date and location for the final global repechage tournament is still to be decided, with the 2021 Rugby World Cup scheduled to kick-off on 18 September.
Fiji qualified for their first ever World Cup tournament after outclassing Samoa 41-13 in the Oceania qualifying final in November.
The draw for the Rugby World Cup 2021 will be held on 20 November in Auckland.