The Canada Border Services Agency is advising last-minute shoppers to prepare for long waits at the border during the holidays.

"It's always busy during December, because there's a lot of cross-border shopping," CBSA superintendent Benoit Brosseau told CBC's All in a Weekend.

He added that this weekend is the busiest of the year because it is the last before Christmas.

He reminded travellers to check online and be aware of limitations for what they can and can't bring across the border.

For instance, Canadians who opt to celebrate Christmas in the U.S. will have to pay taxes and duties on any presents they bring over the border when they return home. He said travellers should bring proof of the value their gifts to help custom agents.

Canadian travellers who spends more than 48 hours in the U.S. have an $800 exemption from taxes and duties, and those staying for 24 hours have a $200 exemption.

Travellers often try to bring too many groceries over the border, according to Brosseau.

"Not a lot of people are aware that there are limits on specific grocery items," he said.

He suggested shoppers check online for grocery limits, especially for food items like dairy and meat.

Those shoppers who go over the limits will face high duty fees. For instance, anyone who buys more than $20 worth of dairy will face a 300 per cent duty rate, according to Brosseau.

"It gets very high and usually people abandon the goods or return them to the United States to avoid paying duties on it," he said.

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