More than 18,000 Costco workers will be walking picket lines in less than two weeks if a labor dispute over wages and benefits is not resolved, according to the Teamsters union. Members voted by an 85% margin to authorize a strike when their current contract expires on Jan. 31, the union announced on Sunday.

Teamsters working for retail giant Costco voted to authorize a strike ahead of a Jan. 31 contract expiration, the labor group said in a statement. The contract covers more than 18,000 Costco

The union, which represents more than 18,000 workers at Costco, said 85% of its members voted to authorize a strike.