Ms Casse and Ms Smales have been campaigning since entering The Edge competition, gaining interest from their Facebook fan page and internet site Gay Express.
"We're incredibly excited to have this opportunity. We're parents to a baby girl and we would love to share our special day as a family," Ms Casse said.
"It means we can be considered equal in New Zealand and we can legally bind our commitment to each other."
The Edge Breakfast Show host Jay-Jay Feeney said she was excited to be part of the event. "We've organised seven successful weddings in the past. We've done stranger weddings, a nude wedding and even hitched people in Las Vegas," Ms Feeney said.
"We've always been very supportive of the law change and we can't wait to throw a double wedding for our same-sex couples who can now be married the same way as everyone else."
On August 19, New Zealand is set to become the 15th country in which same-sex couples can legally marry.