Losses were widespread, with 525 stocks declining, nearly twice the number of gainers. Across the market, 38 stocks hit their daily ceiling prices while 46 fell to their floor prices.

Liquidity on the Ho Chi Minh Stock Exchange, or HoSE, was also relatively weak, with total trading value below VND17 trillion ($644 million).

Within the VN30 basket of large-cap stocks, 28 of its 30 constituents declined. The only gainers were BSR, the ticker of Binh Son Refining and Petrochemical, and SSB of Southeast Asia Commercial Joint Stock Bank, or SeABank.

Stocks linked to Vingroup, Vietnam’s largest private conglomerate, fell across the board. VIC dropped VND4,400 to VND243,300 ($9.22) a share, well below the VND265,000 ($10.04) peak reached the previous week.

VHM fell VND1,100 to VND72,000 ($2.73), VPL lost VND1,500 to VND82,500 ($3.13), while VRE declined VND850 to VND25,600 ($0.97).

Other large-cap stocks also came under heavy selling pressure. GVR fell VND1,700 to VND30,000 ($1.14), MSN lost VND2,200 to VND66,500 ($2.52), TCX dropped VND1,500 to VND38,100 ($1.44), and SSI declined VND700 to VND20,300 ($0.77).

Foreign investors also returned to heavy net selling. They bought about VND1.966 trillion ($74.5 million) worth of shares while selling nearly VND2.812 trillion ($106.5 million), resulting in net sales of around VND845 billion ($32 million).

Foreign selling was concentrated in STB, MBB, VPB, VHM and VNM, among others, while BSR, VIC, PNJ, TCB and VCB recorded net foreign buying.

Notably, the market decline did not prevent Pham Nhat Vuong, chairman of Vingroup and Vietnam’s richest man, from moving higher on Forbes’ global billionaire ranking.

According to Forbes, Vuong’s wealth had fallen by nearly $600 million to about $37.7 billion as of Sept. 11. Despite the decline, he moved up one place to No. 58 among the world’s richest people.

Meanwhile, the fortune of his wife, Pham Thu Huong, fell 1.75% to around $4.3 billion. Huong remained Southeast Asia’s second-richest person but dropped out of the world’s top 1,000 billionaires to No. 1,016.

Capital flows ahead of upgrade: High expectations, rising risks

The sharp Sept. 11 decline came just 10 days before FTSE Russell is due to officially upgrade Vietnam from frontier-market to secondary emerging-market status, effective Sept. 21.

The upgrade has been widely viewed as the most important catalyst for Vietnamese equities in September. According to VnDirect, FTSE Russell’s Aug. 21 announcement of a portfolio containing 27 Vietnamese stocks to be added to FTSE Emerging indices strengthened expectations of passive foreign capital inflows.

However, the upgrade does not necessarily mean large amounts of capital will immediately and simultaneously pour into the market.

Some of those expectations have already been priced in following the VN-Index’s strong rally, which at one point took it toward the 1,900 level.

Pressure for a correction is now coming from several directions.

The first is the international environment, particularly tensions in the Middle East, which have sent oil prices soaring. Although crude prices were down around 3.5% on the evening of Sept. 11, WTI remained around $99 a barrel and Brent at approximately $104.

High oil prices increase transportation and production costs and raise the risk of inflation, directly affecting expectations for monetary policy.

In the United States, markets are currently pricing in around a 70% probability that the Federal Reserve will raise interest rates next week. The yield on 10-year US Treasuries has moved close to 5%, putting pressure on risk assets, particularly stocks trading at high valuations.

Within Vietnam, bank interest rates remain another important variable. Some banks are offering deposit rates of up to around 8.2% a year on small six-month deposits.

If interest rates remain elevated, idle capital may have less incentive to move into equities, while businesses will also face pressure from higher funding costs.

SGI Capital warned in its August 2026 report that the VN-Index was approaching its previous peak while leverage, interest rates and liquidity posed potential risks.

According to the firm, markets typically perform strongly in the six to 12 months before an upgrade, but profit-taking and corrections can emerge during the three to six months afterward.

There are, however, supportive factors.

According to VnDirect, foreign net-selling pressure has eased considerably. Although August marked the eighth consecutive month of net foreign selling, the total was only around VND1.644 trillion ($62.3 million), down 85.8% from July.

This suggests that selling pressure from foreign investors has cooled to some extent. If passive capital begins flowing into the market according to the upgrade schedule, it could provide significant support.

The period through Sept. 21 could therefore continue to see sharp swings. Following a prolonged rally, the market needs time to absorb profit-taking, while investors must simultaneously monitor oil prices, developments in the Middle East, the Fed’s decision, US Treasury yields, exchange rates and domestic interest rates.

In other words, Vietnam’s market upgrade remains a powerful catalyst, but in the short term investors are unlikely to focus on FTSE alone.

After such a strong rally, the market will need greater liquidity and actual capital inflows to sustain its momentum rather than relying solely on expectations.

Manh Ha