The change was made after France decided to withdraw as hosts. The tournament will also feature only 10 men's teams, down from 16 in 2021, eight women's and eight wheelchair teams.
"An IRL board meeting in Singapore has agreed to shift the World Cup from 2025 to 2026 and stage it under a revised format as part of a new calendar to 2030 aimed at capitalising on the growth of the international game," it said in a statement.
The IRL said a decision on the right to host the 2026 edition in the southern hemisphere would be made by the end of the year.
"In addition, it has been decided that the following Women's Rugby League World Cup, after RLWC2026, will be held as a stand-alone tournament in 2028.
"The cycle has also changed for the Men's World Cup, with the next tournament after RLWC2026 to be played in 2030."
