The Dutch defender has joined the Midlands side after prolonged negotiations when both the club and player had previously threatened to pull the plug on the move
Vlaar, who was part of Netherlands' disappointing Euro 2012 campaign, travelled to Villa Park recently for talks with new boss Paul Lambert and despite the Dutch side and even the defender himself suggesting a deal may be off, there has been a compromise in negotiations.
The 27-year-old will undergo medical tests on Monday to seal his transfer after Feyenoord revealed on their club website that the centre-half would be leaving.
The statement seemed to suggest that Feyenoord felt Villa had taken too long to finalise a deal and it appeared the case was closed, but now the move has been made official, Vlaar will become Lambert's fourth summer signing.
Despite securing his dream move, the Dutch international says he will miss the club he made over 100 appearances for.
Vlaar told the club website: "It's a strange feeling to leave Feyenoord, but it's a dream come true to play in the Premier League.
"We [the club and myself] spoke again today and sorted some things out. It was a lively conversation and Aston Villa apologised for the way they acted in the last weeks."
After six years at the club, Vlaar has become something of a key figure at the Rotterdam outfit and is hopeful fans will not look down on him for his decision.
He added: "I can imagine that the Feyenoord fans, at this moment, aren't happy with me, but I hope they understand why I'm leaving."