Perez, 25, is the reigning World Series Most Valuable Player Award winner and one of the team leaders in the clubhouse. The first person Perez told about the deal was his mom, Yilda, who had been robbed at gunpoint in Venezuela two days earlier.
"She cried," Perez said.
Perez, however, was beaming at Tuesday's press conference. Asked how he felt, Perez pointed to his ear-to-ear smile.
"I feel very happy," Perez said.
Perez's original deal signed in 2012 was for a guaranteed $7 million over five years. It also carried three club options that, with bonuses, would have been worth $16.5 million.
"We went into Salvy's previous deal with expectations that obviously he was going to be a terrific player," Royals general manager Dayton Moore said. "We've always believed in him, as a talent, as a person, as a teammate. And he's outperformed that contract. He [was an] underpaid player in the game.
"Salvy is easy to believe in. Salvy is easy to trust. You pull for him, and you enjoy watching him play. We just felt it was an important part of who we are as an organization. We've got the great support from [team owner David] Glass and [team president] Dan Glass and our entire Royals community."
Moore said he was not concerned that renegotiating an existing contract would set precedent in the clubhouse.
"Every player is different," Moore said. "Every negotiation is unique. We take them all case by case. There are no two players that are the same. There are no two situations that are the same. It's a unique situation, one that I'm not sure had presented itself in Kansas City [before]."
The Royals essentially added $36 million of guaranteed money to Perez's pact. The breakdown: Perez will get $3 million in 2017, $7.5 million in '18, $10 million in '19, $13 million in '20 and $13 million in '21.
Manager Ned Yost seemed almost as happy as Perez to hear about the extension.
"It was love at first sight for me when I saw him in [Class A] ball," Yost said. "I've been in Major League Baseball for 25 or 26 years, and I've seen two catchers of All-Star caliber -- Javier Lopez and Salvy. They don't grow on trees. Very tough to find."
Yost, a former catcher, has formed a tight bond with Perez.
"Salvy laughs at this," Yost said, "but at the end of the World Series, I told him, 'You come live with me. You come live with me this winter. I'm going to teach you how to hunt, how to fish.' And I was half-joking, but Salvy says, 'Hmm, let me think about it.'
"But I love this kid! I love all these kids because they give me everything they have every day. What more can you ask for?"
Perez's original deal had been regarded as overly club-friendly and increasingly undervalued for him as years passed. The renegotiation actually started a year ago at this time, but it picked up in recent weeks.
Of the original deal, Perez said, "It was a good deal at the moment, but things changed."
Jeffrey Flanagan is a reporter for MLB.com. Follow him on Twitter at @FlannyMLB. This story was not subject to the approval of Major League Baseball or its clubs.