The 33-year-old is the fifth player to join the initiative, which sees participants donate a portion of their salary to football charities around the world, following in the footsteps of Manchester United's Juan Mata, Bayern Munich's Mats Hummels and USA stars Megan Rapinoe and Alex Morgan.
Inspired by Mata's recent promotion of the campaign, Chiellini contacted Common Goal of his own accord and hopes his involvement will inspire young players to follow his lead.
His e-mail read: "Hello. I'm Giorgio Chiellini, player of Juventus.
"I'm interested to support your program and I would like to give my congratulations to Juan Mata for finding the time and having the idea to support through football people less lucky than us.
"I'm not interested in advertising, I want only to support a brilliant project.
"Sorry for my English. I try to make the best as possible!
"I wait for your answer about complete the registration. Bye, Giorgio."
Speaking after joining the project, Chiellini said: "By joining Common Goal, I hope I can encourage the younger generation of players to think about social responsibility in their lives.
"As professional footballers, we are in a fortunate position compared to much of society. I think it's important we keep this in mind and try to support those less lucky than us where we can.
"This isn't really about my pledge to Common Goal. This is about all of us footballers giving back as a team. Individually our pledges might not change the world, but together we can make a real difference."