The National Institute of Development Administration (NIDA) surveyed 1,163 people during July 4-12 in Bangkok and its vicinity on countries in ASEAN to which they wish to travel.
Over one on three respondents -- about 36 per cent -- chose Singapore, followed by Laos at 15 per cent, and Malaysia at 11 per cent.
Thailand ranked fourth at 9 per cent, followed by Vietnam at 6, Myanmar at 5, Brunei Darussalam at 4, and Philippines at 3 respectively.
Association of Thai Travel Agents president Sisdivachr Cheewarattanporn said the result was not unexpected. He viewed that European and American travellers would also pick Singapore, as it is a developed country and has invested in new tourist attractions.
He commented that Thailand still lacks investment on new tourist destinations. The country has natural sites as major selling points, but facilities and maintenance of those sites need improvement as well.
Mr Sisdivachr noted also that Thailand's political instability is a main factor for tourists' decisions to come to Thailand.
Travellers' decisions will also be impacted by today's Constitution Court's ruling on whether the Pheu Thai Party-led government's draft to amend to amend the constitution is illegal, he said.
Tour entrepreneurs in China and Japan have been asking of the situation and closely monitoring the issue, the ATTA president added.