The party has received an invitation to a meeting later this month with the consortium of TV networks that produce the debates.
The letter from consortium chairwoman Jennifer McGuire says it is the goal of the networks to finalize details of the English and French debates as soon as possible.
Green party spokesman Julian Morelli, who has been involved in discussions with the consortium of broadcasters, says he considers the letter confirmation of May's participation.
It is now just a matter of determining the format of the debates at the April 24 meeting in Toronto, Morelli said.
McGuire was not immediately available for comment.
For weeks there has been speculation as to whether May would be invited to take part.
She participated in 2008 but was denied a spot in the 2011 — the year she won a seat in Parliament.
The consortium of broadcasters includes CTV News, Shaw Media, CBC News and French-language Radio-Canada.
A federal election is expected no later than this fall.
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