The new multi-year deal will see the speedy number seven remain part of the Essendon’s fabric until the end of the 2018 season.
The 19 year-old said his decision to recommit was based on his belief the current playing list can push for finals success.
“Since I walked into the footy Club everyone has been extremely welcoming, from the players right through to the support staff,” Merrett said.
“My decision to re-sign was based on the fact I believe we have a really tight group who want to achieve success together, we want to play finals and win finals.
“Essendon is where I want to play my footy. We have great coaches and development staff that I believe will provide me with the opportunity to get the best out of myself both on and off the field.”