Former Manchester City, Stoke and Mansfield Town frontman Greenacre has penned a two-year deal from League One club Tranmere Rovers, where he has been top scorer for three of his last four seasons.
Phoenix coach Ricki Herbert and chief executive Tony Pignata targeted Greenacre prior to a recruiting mission to the United Kingdom in March after Golden Boot winner Shane Smeltz joined expansion club Gold Coast United.
Greenacre and wife Lynsey are scheduled to arrive in Wellington in the first week of June ahead of the new A-League season, which begins in early August.
"I can't wait," said Greenacre. "It wasn't a tough decision at all, certainly not from a football perspective. The more I learned about the club and about Wellington from Tony the more it appealed.
"I'm not so much a target man as the sort of player who can hold the ball up, score what some people might call the 'ugly' goals, I guess - get in and around the box and on the posts and scramble them in.
"I'm not the sort of player who is going to take the ball on halfway, beat five guys then curl the ball past the keeper. It's more about using my knowledge and experience to get into good scoring positions and to be clinical in finishing."
The Phoenix, who finished sixth last season just two points adrift of a place in the play-offs, will continue to search for a second striker to compliment Greenacre.
"We've had tremendous feedback from a lot of people that we've spoken to about Chris, from coaches and managers to his fellow players," Pignata said.
"His qualities as a professional are second to none, and that was clear to Ricki and me within the first 10 minutes of meeting him. We're very excited about getting him here to join the Phoenix.
"Chris has a proven pedigree as a striker and we're certain he will fit in very well at the Phoenix."