Construction unions pulled pickets from Ralph Wilson Stadium this week, ending a 10-day demonstration against the use of non-union contractors.
"We reached an agreement with the construction manager," said George Harrigan, a business agent with the Teamsters Local 449.
Union and Erie County officials wouldn't discuss the terms of the agreement, and officials of the Buffalo Bills didn't return phone calls seeking comment.
The Bills are renovating the Orchard Park stadium with new restrooms and luxury suites.
The $63.25 million state-funded project faces an August deadline, in time for the first pre-season game.
The presence of non-union contractor Tom Greenauer Development Inc. ignited the demonstration last week, union officials said. The Elma company has been the target of construction unions' organizing campaigns and unfair labor practice charges.
Greenauer will continue working at the site until its work under contract for the Bills is complete, Harrigan said.
The construction company wouldn't comment.
The Bills have said unionized companies will perform 95 percent of the stadium project. But union officials said that the majority of the site-preparation work they saw being conducted in the project's early stages was by non-union firms.
Between 50 and 200 pickets showed up outside the stadium's entrance each day of the picketing and delayed contractors' trucks entering the site, union officials said.
Police arrested two pickets, one for breaking the window on a truck entering the site and one for failing to let a contractor's vehicle pass.
County Legislature Chairman Charles Swanik played an intermediary's role in resolving the dispute.
"We believe this issue needed to be settled," he said.
The Legislature had recommended that the Bills sign a no-strike agreement with the building trades for the project.