The seventh-generation member of the Flying Wallendas spent months getting the necessary permissions from Canada and the United States for the cross-border stunt.
Organizers told a news conference in Niagara Falls, Ont., on Wednesday that the contracts have been signed and the date set.
Wallenda's stunt will merge two pop culture traditions — his own family's death-defying feats on the high wire and the daredevil acts at Niagara Falls that date back more than 100 years.
It took an act of the New York legislature and persistent lobbying of Canadian parks officials to make Wallenda's planned wire stunt a possibility.
The Niagara Parks Commission board gave its thumbs up to Wallenda in February, reversing an earlier decision against the stunt.
"Not only is it a dream but we had to change two laws in two countries that were over 100 years old," Wallenda said.
"This is clearly a once-in-a-lifetime thing."
Niagara Parks chairwoman Janice Thomson had said the approval was a "unique one-time situation" and that Wallenda was able to prove he had proper controls and safety measures in place.
She also said the commission would only consider requests for such events from skilled professionals once every 20 years.
Wallenda's walk across the falls on a five-centimetre diameter steel cable is expected to be televised live.
Tony Baldinelli, a spokesman for the Niagara Parks Commission, said that Wallenda will cross over a portion of the Canadian Horseshoe Falls as he walks from one side of the gorge to the other.
A study has suggested that the television coverage of the event could help generate a $120-million shot in the arm to the Niagara economy.