Thailand could lose up to 200,000 foreign visitors and $US293 million ($A382.83 million) in tourism revenue this year, the head of its tourism authority says, following a series of deadly blasts in tourist towns last week.
The wave of attacks in places including the seaside town of Hua Hin and the island of Phuket, is the biggest challenge to an industry that has weathered more than a decade of instability and bounced back from violence over recent years.
Yuthasak Supasorn, governor of the state Tourism Authority of Thailand, said the attacks could result in long-term losses in terms of tourist revenue and arrivals, mainly from other Asian countries.
"By the year end, there could be about 100,000 to 200,000 travel cancellations," he said in a statement.
"That would cost about 5.08 billion baht to 10.16 billion baht [$A190.76 million to $A382.83 million]."
Tourism accounts for 10 per cent of Thai gross domestic product and is one of the few bright spots in an economy that has struggled under the stewardship of a military government that seized power in a bloodless coup two years ago.
The southeast Asian nation had been expecting a record 32 million visitors in 2016, with expected revenue of 2.41 trillion baht.
Narongchai Wongthanavimok, chief financial officer at national carrier Thai Airways, Thailand's national carrier, said on Friday the bombings would hurt business and consumer confidence.
No group has claimed responsibility for the Thursday and Friday attacks that killed four people and wounded dozens, some of them tourists.
Police said on Monday said they had arrested one man for arson.
DFAT is advising Australians to exercise a high degree of caution in Thailand, and recommends they do not travel at all to the areas of Yala, Pattani, Narathiwat and Songkhla.
Other embassies in Thailand have warned their citizens to stay vigilant and some have warned that there could be more attacks.
A bomb attack on a Bangkok shrine on August 17 last year killed 20 people, more than half of them Asian tourists, but it did not seriously undermine the industry.
