Footfall was down 6.2% on high streets across the UK.
The figures are an early sign that online shopping continues to dominate the traditional Boxing Day sales.
There are, however, indications that some shops did better Boxing Day business in 2024.
The Emporium of Loveliness, a Swindon charity shop, told BBC West that people were increasingly searching for preowned wares to keep costs down.
Founder Jo Heaven said: “I think it’s going to be a tough year next year for some shops, and I think we particularly are going to do quite well.
“People are looking for bargains and they want to get a lot more for their money.”