The 33-year-old, who made his debut against Tottenham on January 12, 2003, is a one-club man having made his way through the junior ranks at Goodison and featured in the 1998 FA Youth Cup-winning side.
Osman has made nearly 400 appearances for the Toffees and they will honour his decade of service with the home friendly on August 3, which will kick off at 4pm.
"It feels very weird (having a testimonial). The attention is all on you," Osman told evertonfc.com.
"I have pretty much gone through my career without asking for attention so it will be strange knowing I will be walking on to the pitch and everyone is going to be pointing at me. But it's a great honour to get a testimonial, and I will certainly be enjoying the day."
Osman's career was almost derailed by a serious knee injury in 2001 that kept him out of action for almost a year.
During that time he had to watch on as fellow academy graduates such as Tony Hibbert nailed down first-team places, but his neat feet soon jinked their way into then-manager David Moyes' plans.
After successful loan spells at Carlisle United and Derby County, Osman earned his first start at Wolves in May 2004 - scoring his first goal for the club after just three minutes.
He never looked back after that moment and has scored 54 goals for the blue half of Merseyside, becoming a club stalwart under Moyes and, more recently, Roberto Martinez.
Everton have also confirmed that they will take on local rivals Tranmere Rovers at Prenton Park on July 22, with that friendly set for a 7.45pm kick off.