The baht gained as much as 0.8 percent to 31.09 per dollar as exports in August grew at their fastest pace in five months, improving the chances the country can emerge from recession in the third quarter despite some caution on global demand.
The Indian rupee rose after the central bank eased norms for providing swaps to banks that are borrowing funds overseas.
The Taiwan dollar gained on exporters and foreign financial institutions. The South Korean won also advanced on sustained stock inflows and exporters' demand.
The Indonesian rupiah turned firmer on some demand from foreign banks and as local banks bought it on behalf of exporters, traders said. A Jakarta-based trader said state-run banks also bought the rupiah.
Adding to support to the ailing currency, foreign investment in Indonesian government bonds rose to 289.24 trillion rupiah ($25.18 billion) as of Sept. 25, or 5.23 trillion rupiah higher than at the end of August, Finance Ministry data showed.
In the past two weeks, sentiment on emerging Asian currencies has improved and long positions in the Chinese yuan are at their largest in more than three months, a Reuters poll showed. A major factor has been the US Federal Reserve's unexpected decision last week to maintain monetary stimulus.