The young gun was taken by the Crows with pick 11 in the 2015 National Draft and has totalled 60 senior games.
The 22-year old is coming off a breakout 2019 campaign where he was predominately used across half-back, averaging 18.2 disposals from his 17 appearances.
Crows general manager of list and strategy Justin Reid said the best was yet to come for the young gun.
“He is an outstanding young footballer but most importantly a young man of high character,” Reid told afc.com.au.
“Wayne is an emerging leader who is eager to help others and he is determined to make a positive contribution, not just inside our Club but in the broader community.
“We look forward to seeing him continuing to develop as both a player and person in the years to come, and we are committed to helping him realise his potential.”
Milera was thrilled to secure his future at West Lakes.
“I am working on my leadership and want to improve in that area so I will keep building and setting a good example,” Milera said.
“We have a really talented bunch of guys and it’s an exciting time, and I definitely want to be part of the team success that is ahead of us if we keep working hard.”