The 25-year old Scotland international departed Ibrox after deciding against switching his contract over to the newco and has now signed a four-year deal with the Toffees as the 'Gers exodus continues.
Naismith, who is still sidelined by a knee injury, was delighted to be signing with Everton and is looking forward to getting himself to full fitness in a bid to get his career up and running again.
"It is a great honour to be joining a club of Everton's wonderful history and to have the chance to play with such a talented group of players in the world's best league: the Barclays Premier League, in front of such a passionate group of fans," Naismith told the club's official website.
"I look forward greatly to working with the manager David Moyes and all the staff at Everton and working hard to deliver on the pitch to repay their, and the chairman Mr Kenwright's, faith and belief in me."
Moyes added: "We are delighted that Steven has agreed to join us. He will be an excellent addition to the players we already have and we look forward to him being fit and ready to play at the start of the season.
"He is an established international who can play in a number of positions. He has a flexibility we always like in our players and which will hopefully prove to be very useful for us."