ReplayFX 2017 was the third real world ToonFest event hosted during the summer of 2017 to celebrate the 14th anniversary of Toontown. The event took place at a convention called ReplayFX in Pittsburgh, Pennsylvania from July 27, 2017 to July 30, 2017. Toontown Rewritten updated fans that could not make it to the live event throughout social media and mostly with Snapchat, through the account "ToontownTV". Unlike previous years, the event was broadcasted live on YouTube and Instagram for the first time ever.
Toontown Rewritten uploaded two YouTube videos consisting of a special interview with Jesse Schell and Shawn Patton, and footage of the traditional Toontown pie toss. New ToonFest 2017 Blue Shirt and ToonFest 2017 Pink Shirt items were released for all Toons by redeeming the code "replayfx2017". Attendees could also redeem special codes they received at the event for an exclusive ToonFest 2017 Blue Attendee Shirt and ToonFest 2017 Pink Attendee Shirt.
On October 26, 2017, Toontown Rewritten started sending out Member Mailers until March 31, 2018 to offer players a chance to receive their very own trading cards from ReplayFX. The trading cards introduced this year consists of Fluffy, the Shticker Book, and Goon. Along with the trading cards, players also received a mini Toontown poster.
- March 19 - Announcing ToonFest at ReplayFX 2017 (posted by The TTR Team)
- May 22 - Meet Developers of Toontown Online (posted by The TTR Team)
- June 26 - ReplayFX Update: Take Your Vacation to the Tooniverse! (posted by The TTR Team)
- July 19 - ReplayFX Update: Awesome Activities for Everyone (posted by The TTR Team)
- July 27 - Welcome to the New Toontown Website - ToonFest 2017 (posted by The TTR Team)
- July 28 - The Main Event - ToonFest 2017 (posted by The TTR Team)
- Jesse Schell and Shawn Patton participated in the main ToonFest panel to answer questions from attendees.
- The winner of the Toontown Species Election was announced during the main ToonFest panel on July 28, 2017, having gone through the voting sessions for a year since the event's announcement made at OMG!Con 2016.
- This is the first real world event that involved visiting another area near the convention center. ToonSeum was a museum mainly known for showcasing cartoon history.