The World Triathlon Corporation has confirmed the resort community will take over the event from Penticton, which bowed out last year after holding the Ironman for 30 years.
Tourism Whistler president Barrett Fisher says the race is a natural fit for the resort community.
"Whistler has a number of natural assets when it comes to our mountains, our lakes and valley trail infrastructure which make it an ideal location to host such an event," said Fisher.
Kelowna and Huntsville, Ontario, were also in the running to host the Ironman race, which has athletes competing in a course that includes cycling, swimming and running.
Kelowna's Mayor Walter Gray says despite the loss, Kelowna remains committed to establishing itself as a centre for multi-sport excellence.
"We wanted it very badly for Kelowna we're naturally disappointed in the announcement that it's going to Whistler - but good on Whistler - and congratulations to them," said Gray.
Penticton Mayor Dan Ashton says the World Triathlon Corporation made a "predatory" decision by scheduling the Whistler Ironman next year, on the same day as Penticton's new extreme race event.
Penticton gave up the gruelling triathlon -- which attracts thousands of athletes annually -- in order to work with another company and focus on a new challenge series also set for Aug. 25.
Last year Penticton held its last Ironman on Aug. 26, 2012. The first Whistler Ironman Canada event will happen on Aug. 25. The event will then be held in July for the following four years.