Merrett, who will be the 41st skipper of the Bombers, will be supported by Andrew McGrath who has been appointed vice-captain.
Since his debut, Merrett has played 184 games with the Bombers, becoming an integral part of the Essendon side.
Speaking after the announcement, Merrett said it was an "honour" to be named skipper, thanking his predecessor Heppell for his time in the role.
“It is a huge honour to be selected as the next Captain of Essendon,” Merrett said.
“Some of the finest names in Australian football have been captains of Essendon. From Reynolds to Clarke, Daniher, Hird and Heppell, it's humbling to join this list of champions of Essendon.
“This is a great club with a great future, and I look forward to playing my role as an on-field and off-field leader. I feel very humble to have been given this opportunity, and I thank Brad Scott, the coaching staff, football department and my team-mates for their confidence.
“This is a privilege which I am very grateful for and am very much looking forward to. There's great energy around the group. With Andy and I as captains, supported by a group of emerging leaders, we are all united and aligned in our vision to take us back to being a successful football club.
New era, new leaders.
Congrats, Zach + Andy.
— Essendon FC (@essendonfc) February 21, 2023
“This is a journey for all Essendon people – we're bringing everyone along for the ride and we are working really hard to make our members and supporters proud of this team again.
“I also thank Dyson Heppell who is a great mate, and who has led the Bombers with such distinction over six seasons. He has worked hard behind the scenes to get us to where we are today, and I hope we can reward his commitment with some great wins in 2023.”
Essendon will not appoint any other leaders for this season.