The Stock Exchange of Thailand (SET) says it is monitoring the escalating trade war and stands ready to deploy circuit breakers should the situation worsen.
Temporary measures are in place to reduce market volatility, SET president Asadej Kongsiri said on Wednesday, emphasising that circuit breakers would only be used in cases of extreme market disruption and panic selling.
According to protocols, trading is halted for 30 minutes if the index drops by 8%. A further decline of 15% triggers another 30-minute pause, and a 20% drop would suspend trading for an additional hour.
During the recent escalation of the trade war, the SET responded by tightening market mechanisms. On Monday the bourse announced a ban on short selling of all securities, excluding designated market-makers on the SET, the Market for Alternative Investment (MAI), and the Thailand Futures Exchange (TFEX).
These measures proved effective as several regional markets recorded steep sell-offs, but Thailand's equities fared relatively better, said Mr Asadej. Among SET100 companies, which represent 70-80% of the total market capitalisation, only two stocks hit their floor during intra-day trading, both of which rebounded before the market closed.
The market dropped 4.5%, outperforming regional peers, he said.
"We have the circuit breaker mechanism in reserve, which is only used when absolutely necessary. So far, our adjustment of the ceiling and floor limits has proven sufficient," said Mr Asadej.
The SET closes for the Songkran holiday on April 14-15, but global markets remain open. The bourse plans to continue monitoring any changes to US tariff policy, he said.
The temporary ban on short selling and other stabilisation measures are expected to be lifted on April 16, though further actions may be considered if global volatility persists, said Mr Asadej.
At the end of March, the SET index closed at 1,158.09 points, down 3.8% from the previous month, largely due to the impact of the recent earthquake. The decline was sharper than most regional markets, bringing the year-to-date loss to 17.3%.
Soraphol Tulayasathien, senior executive vice-president of the SET, said the earthquake severely affected the transport, real estate, insurance and construction sectors, raising investor concerns about potential debt repayment challenges for affected firms.
However, financial indicators suggest most listed companies remain fundamentally strong and capable of weathering the crisis, he said.
With the SET index slumping, market valuations have become attractive. Some listed companies have started share buybacks to restore investor confidence, while value stocks now present limited downside risk, said Mr Soraphol.
The average daily trading value of the SET and MAI was 38.5 billion baht last month, down 10% year-on-year. For the first quarter, the average daily trading value was 42.8 billion baht, a dip of 6.3% year-on-year.
Foreign investors were net sellers of 21.9 billion baht in March and 40 billion baht for the first three months.
Since the Trump reciprocal tariffs were announced, the Thai index has dropped 8.4%, mirroring movements in other regional indices.
As of the end of March, the bourse's forward price-to-earnings (P/E) ratio was 12.2 times, above the regional average of 11.4 times. Historical P/E was 15.2 times, compared with the regional average of 13.9 times. The dividend yield was 4.24%, higher than the regional average of 3.34%.
Last month the average daily trading volume on TFEX was 519,619 contracts, up 7.1% from the previous month.
However, the volume has averaged 463,656 contracts year-to-date, down 4.2% year-on-year due to declines in Single Stock Futures and Gold Online Futures.