The 22-year-old restricted free agent appeared in 42 of Ottawa's 48 regular-season games in 2012-13, registering a career-high 19 points (five goals, 14 assists) to go along with a plus-9 rating and 39 penalty minutes
Wiercioch led all the club's defencemen with three power-play goals.
The Burnaby, B.C., native was recalled by the Senators from the club's American Hockey League affiliate in Binghamton after the NHL lockout and remained with Ottawa for the duration of the season.
In 50 career NHL games, Wiercioch has 21 points (five goals, 16 assists) and 43 penalty minutes.
Ottawa's second-round selection (42nd overall) in 2008, Wiercioch was member of the Binghamton Senators team that captured the AHL's Calder Cup in 2011.