Watkins had the procedure done sometime before the Super Bowl for the injury that was suffered in a Week 13 win over the Cleveland Browns, according to sources. He had three catches for a season-low 11 yards in that game, but played every offensive snap.
He played 72 of 80 snaps in the Bills' next contest, a Dec. 7 loss to the Denver Broncos, in which he had seven catches for 127 yards. Watkins was taken off the team's injury report the following week.
It's unclear if the procedure will affect Watkins' availability for voluntary offseason workouts, which begin April 6. The Bills will hold a voluntary veteran minicamp April 28-30 because they have a new head coach, Rex Ryan.
In his rookie season, Watkins proved to be Buffalo's top receiver, leading the team in targets (128), yards (982) and receiving touchdowns (six). He was also tied for second on the team in receptions (65). However after starting the season with five touchdown catches in his first eight games, he had just one in the second half of the season.
In addition to his hip injury, Watkins played through broken ribs that he suffered in the preseason and also missed practice time in early November with a groin injury, but played in all 16 of the team's games.
Watkins figures to again be a focal point of a Bills offense that now features a backfield of newly acquired LeSean McCoy and Bills mainstay Fred Jackson.
Buffalo remains unsettled at quarterback, the Bills added Matt Cassel to battle EJ Manuel to be the top quarterback following the retirement of Kyle Orton.
The Bills are without first- and fourth-round selections in the upcoming draft after dealing those picks to acquire Watkins in a draft-day trade last May.
Information from ESPN's Josina Anderson and ESPN.com Bills reporter Mike Rodak contributed to this report.
Is Sammy Watkins injury-prone?
ESPN NFL Insider Field Yates discusses the news that Bills WR Sammy Watkins had offseason surgery on the area near his hip.