For nearly three years, the trade was simple: mainland Chinese investors poured money into Hong Kong-listed stocks like clockwork, month after month, pushing the Southbound leg of Stock Connect into record territory. That streak just snapped.

May 2026 marked the first monthly net selling by mainland investors in Hong Kong equities via the Stock Connect program in nearly three years.

The numbers behind the shift

Full-year 2025 saw Southbound net inflows hit a record HK$1.4 trillion. The first quarter of 2026 saw HK$220.9 billion in net buying despite turbulent conditions.

On March 5, 2026, mainland investors dumped a record HK$27.7 billion ($3.5 billion) in a single day through Southbound Stock Connect. Geopolitical tensions in the Middle East were the trigger. Then, just four days later on March 9, they reversed course with a record single-day net buy of HK$37.2 billion.

What’s driving the pullback

Beijing has been increasing scrutiny on offshore brokers, with firms like Futu and Tiger Brokers facing restrictions on their trading activities. These platforms had become popular conduits for mainland money flowing into Hong Kong markets, and squeezing them effectively narrows the pipeline.

If Beijing continues tightening oversight of offshore trading platforms, it could further reduce the flow of mainland capital into Hong Kong, making the mechanics of actually deploying capital more cumbersome even if investor sentiment improves.

Background: how Stock Connect became the main artery

Stock Connect, launched in 2014, links mainland Chinese exchanges with Hong Kong’s market. The Southbound leg lets mainland investors buy Hong Kong-listed shares, while Northbound lets international investors access mainland stocks.

What this means for investors

Mainland buying had been a consistent source of demand for Hong Kong equities, and its absence could lead to wider bid-ask spreads and increased price volatility. Stocks that benefited most from Southbound inflows are particularly exposed.

The pattern has shifted from steady accumulation to volatile, event-driven positioning, as evidenced by the HK$27.7 billion single-day sell and the HK$37.2 billion single-day buy occurring within the same week in March 2026.