The University of the Thai Chamber of Commerce (UTCC) has increased its forecast for GDP growth in 2017 to 3.9%, up from the previous forecast of 3.6% as hefty exports and a growing tourism industry support the upgrade.
The UTCC also forecast exports this year to grow 7.5% in line with the Commerce Ministry outlook.
The university forecast GDP growth in 2018 and 2019 at 4.2% and 4.5%, respectively.
Thanavath Phonvichai, UTCC vice-president for research, said the recovering global economy has pushed demand for Thai products higher, increasing exports, while removal of the International Civil Aviation Organization's red flag for Thailand's aviation safety should help boost the tourism industry.
"The red flag removal as the high season for tourism begins should help increase revenue in that industry sharply and support economic growth," said Mr Thanavath.
He said Prime Minister Prayut Chan-o-cha's announcement of a clear road map for a general election in May next year has also helped increase confidence among Thai and foreign investors, and supported the Stock Exchange of Thailand index breaking the longtime barrier of 1,700 points.
That momentum implies rising purchasing power amid the middle class, which should also help pace the economy, said Mr Thanavath.
The government's welfare policy to support the poor by granting 200 baht per month to low-income earners was also expected to increase purchasing power.
"The government budget will also inject billions of baht into the economy, helping to spur growth," he said.
Several events and holidays in the last quarter of this year should help push GDP growth for the period to 4.3%, making GDP growth for the whole year tally 3.9%, up from the previous forecast of 3.6%, said Mr Thanavath.
He said the UTCC would keep an eye on possible economic stimulus measures during the last quarter of the year.
"If there are any new measures, such as previous ones to encourage people to go shopping for a tax deduction, it would make us raise the GDP forecast again to exceed 4%," said Mr Thanavath.
He said the government's flagship policy to attract new investment in the Eastern Economic Corridor should help increase inflows in infrastructure by 200-300 billion baht, supporting economic growth of over 4% for the next two years.
The UTCC expects the Bank of Thailand to start raising the policy interest rate by the second quarter of next year in line with US Federal Reserve actions.