"At this point, holiday merchandise is already in the country, so the direct impact of new tariffs won't be seen until the season is over," Jonathan Gold, National Retail Federation vice president for supply chain and customs policy, said in a statement.
U.S. ports handled 1.95 million 20-foot-long cargo containers, or their equivalents, in November, up 8 percent from last year, according to the National Retail Federation, citing Global Port Tracker data. That was the highest total since August, when retailers scrambled to get ahead of the tariffs that hit Chinese goods in September.
December volume is expected to fall by 8.9 percent to 1.79 million as the tariffs hit and the usual post-holiday drop-off occurs, the NRF said.
"Tariffs are bad for both consumer and business confidence, and we hope that the December tariffs will be canceled or postponed as a sign of good faith," Gold said. "We need a deal with China as soon as possible so we can bring an end to the trade war that has put a drag on the U.S. economy for far too long."
The more than 21-month-long trade war has slowed the U.S. economy, but growth was still a robust 2.1 percent in the third quarter, according to a second reading published by the Commerce Department on Nov. 27. The economy got more good news on Friday, with the release of the strong November jobs report. Economic growth was 3.1 percent in the first quarter of the year.
The U.S. and China continue their efforts to reach a partial trade deal, which Beijing hopes to get done before tariffs increase on Sunday.
On Friday, China waived tariffs on U.S. soybeans and pork as a sign of goodwill as talks between the two sides remain ongoing. China has called on the U.S. to roll back tariffs as part of a phase one agreement, but President Trump has said he has no plans to do so.
The U.S. has levied tariffs on more than $350 billion of Chinese goods. China has placed its own tariffs on $150 billion of U.S. products.