Based on the volume of foreign capital under management in 2025, there were $2.95 trillion of overseas assets in Hong Kong compared with $2.946 trillion in Switzerland.

The study said Hong Kong's greater volume -- up 10.7 percent on the previous year -- was driven by "mainland China inflows, strong IPO activity, and equity market gains".

Switzerland saw a 7.6-percent increase in the same period.

Cross-border wealth flows intensified in 2025 despite geopolitical tensions and trade uncertainties, increasing by 8.4 percent to reach $15.7 trillion worldwide, as investors sought to diversify their assets.

"We are seeing wealth creation, cross-border capital flows, and investment ecosystems increasingly concentrate into a smaller number of globally connected hubs," said Michael Kahlich, a co-author of the study, from BCG in Zurich.

"Hong Kong's rise reflects the growing gravitational pull of Asian wealth and capital markets."

Switzerland, though, remains a key financial centre, offering stability and neutrality in an uncertain geopolitical context, the study said.

The Swiss Bankers Association told AFP that the development had taken shape over several years, with asset growth in China being "exceptionally strong", from which Hong Kong "directly benefits".

Swiss banks "are present there themselves", it added, as Asia is one of their growth priorities.

"For Switzerland's future, competitive framework conditions are particularly crucial," the association pointed out, adding that it was "essential that regulation remains targeted".

The Hong Kong government welcomed the study's findings.

"While global economic gravity shifts eastward, geopolitical tensions further highlight Hong Kong's role as a safe harbour, reflecting Hong Kong's appeal as an international financial centre," said the secretary for financial services and the treasury, Christopher Hui.