Wallace, a fourth-round pick and 107th overall, was an all-conference lineman at Texas A&M last season. He will back up veteran starter Eric Heitmann on the 49ers' revamped offensive line.
Balmer, a defensive lineman from North Carolina, was the 29th overall pick. Earlier this week, general manager Scot McCloughan said he was confident he would have all six of the 49ers' draft choices in camp on time.
San Francisco has its first team meeting on Thursday afternoon, with its first practice Friday at its training complex.