In return, the Mariners get shortstop Ronny Cedeno; first baseman Jeff Clement, a former No. 1 draft choice; and three right-handed minor league pitchers -- Nathan Adcock, Brett Lorin and Aaron Pribanic.
Wilson, a hot commodity in rumors about Friday's trade deadline, was the key to the deal with Cedeno.
"This was an opportunity for us to acquire a veteran shortstop, a former All-Star player with leadership qualities and above average defensive skills," said Seattle General Manager Jack Zduriencik.
The Mariners (52-48) are third in the American League West, 7 1/2 half games back of the frontrunning LA Angels (59-40), while Pittsburgh (43-57) is last in the NL Central, 10 1/2 games back of the first place St. Louis Cardinals in the NL Central.