LONDON — The love affair between U.S. consumers and European fashion brands may be heating up, but like most other relationships, it’s loaded with risk, misunderstanding and unmet expectations.

According to a new white paper called “Dressed for America: The U.S. Opportunity for U.K. and European Fashion Brands,” U.S. customers are particularly hungry for European handbags and footwear, but they often abandon their online shopping baskets due to unexpected charges and confusion over sizing or returns.

The paper, published this week by SoldThrough, a Texas-based provider of third-party logistics, said more than half of American adults, or 157.7 million people, buy from European fashion brands, representing an estimated $34.5 billion in annual spend.

Some 81 percent of consumers say those European brands stand out compared to domestic labels for “better materials, sharper craftsmanship, and stronger value for money.”

Despite shoppers’ enthusiasm, European brands are still finding it difficult to grow in the U.S. due to barriers such as high shipping costs, sizing confusion, complicated returns, long delivery times, and unexpected duty and customs charges.

The paper said 78 percent of U.S. consumers face at least one “avoidable barrier” when purchasing European fashion.

“The research reinforced what we already knew, that the American consumer craves European product, and that they’re willing to spend on it. There is not a demand problem, there is an access and logistics problem, with de minimis having a massive impact,” Dan Cate, founder and chief executive officer at SoldThrough, said in an interview.

“We talk to European brands all the time that are losing sales at checkout because the customer makes it all the way through the process, and then they’re hit with a random $60 or $80 charge at the very end,” Cate added.

The research was based on an online survey of more than 2,000 U.S. consumers by Research Without Barriers in August.

The paper highlighted that American consumers “overwhelmingly” expect to buy European fashion through a “U.S.-based experience,” with 93 percent of U.K. and continental European fashion purchases taking place through U.S. retailers, department stores, marketplaces, or a brand’s own U.S. website, rather than directly from Europe.

It also pointed out that U.S. customers aged 25 to 34 are the biggest buyers of European brands, while their parents and grandparents, aged 55-plus, are more loyal to U.S. ones.

Regionally, there is more demand for European brands in the South than on the West Coast, while the Midwest is “the least engaged region” overall. In the Northeast, customers prefer brands from France and the U.K., while the South favors Italian fashion.

The paper argued that if certain challenges can be addressed, European sales in the U.S., the world’s largest apparel market worth more than $373 billion annually, will skyrocket.

It pointed out that an estimated 71.9 million U.S. adults are not spending anything on European fashion, representing a potentially untapped market of $15.7 billion.

SoldThrough works with more than 50 national and international brands, including Mint Velvet, Charles Tyrwhitt, Paul Costelloe, Chinti & Parker, Osprey London and PDPaola, connecting them to e-commerce platforms and marketplaces at stores including Nordstrom, Bloomingdale’s and Macy’s.

At the mass end of the market, it works with Target, Walmart, Amazon and Kohl’s. In some cases, SoldThrough also promotes its partner brands with targeted campaigns and strategizes for growth.

Cate believes there is room to grow and stretch beyond the U.K. and continental Europe.

“I think there are some amazing brands coming out of Scandinavia, Canada and South America. We also have our European brands asking us to help them work with John Lewis online and Zalando,” he said.