Turnover was as brisk as Bt72 billion.
Trinity Securities foresees a further increase in the Stock Exchange of Thailand index.
Trinity has also revised upward its projection, targeting the SET index to hit 1,800 points from an earlier forecast of 1,650.
Foreign investors are net-buyers of Thai stocks in March, with month-to-date net purchases of Bt5.33 billion, against Bt17 billion net-sells last month.
Japan yesterday reported the 0.2 per cent growth in the fourth quarter, while China's export growth in February was higher than expected. Unemployment benefit claims in the US also dropped.