Shams Charania of The Vertical first reported details of the free-agent deal. Financial details weren't immediately announced.
Simmons thanked the Spurs on Saturday:
On Saturday, Adrian Wojnarowski of ESPN reported the deal was worth $6.3 million, $6 million, and $5.7 million, with a partial guarantee of $1 million in the final season.
He began the offseason as a restricted free agent, but the Spurs renounced their rights, which allowed him to sign anywhere without San Antonio having the right to match the offer.
Simmons' journey to become an important role player in San Antonio was unique. He went undrafted out of the University of Houston in 2012 and eventually paid for a tryout with the Austin Toros, the Spurs' D-League affiliate, before working his way onto the NBA roster.
The 27-year-old Texas native hasn't put up monster numbers over his first two seasons. He's averaged 6.1 points, 1.9 rebounds and 1.4 assists per game while shooting 45.1 percent from the field across 133 appearances, including just 10 starts.
His impact goes beyond those seemingly mundane statistics, though.
He averaged 10.5 points when asked to take on a more prominent role in this past season's playoff run due to injuries to Kawhi Leonard and Tony Parker. The deep Spurs roster just didn't give him those opportunities much during the regular season.
Simmons is also a top-tier perimeter defender. He ranked eighth among shooting guards in Defensive Real Plus-Minus during the 2016-17 season, according to ESPN.com.
While the guard is now entrenched at the NBA level, he doesn't forget about the hurdles he had to jump before getting there, as he explained to Lorne Chan of Spurs.com.
"I try to focus on moving forward, but I still think back to that tryout all the time," Simmons said. "Walking in with all those guys, trying to figure out a way to stand out."
Heading to Orlando will come with a lot of added pressure. He was an unheralded member of the Spurs who was allowed to shine in a limited role. Now he'll be expected to play bigger minutes and produce at both ends of the floor consistently as both a shooting guard and a small forward.
That said, it's also a golden opportunity to cap his memorable journey to the NBA by becoming a high-impact player with the Magic. The defensive skill is there and his offensive numbers should increase with more time on the ball in his new home.