Expect long lineups this weekend at U.S.-Canada border crossings as a new set of duty-free shopping limits kick in Friday.

U.S. retailers in towns close to the Canadian border expect a flood of sales as the feds significantly boosted shopping limits for stays longer than 24 hours.

For Canadians staying more than a day, the limit is increased from $50 to $200 and the limit was bolstered to $800 for visits longer than 48 hours.

The laxer restrictions are making some Canadian retailers nervous as many Canadians already make the trek south of the border for cheaper goods. A recent report from the Bank of Montreal estimates cross-border shopping costs the Canadian economy around $20 billion a year in lost sales.