The economy is expected to grow by an average of 4.7% during 2018-22, driven by the government's hefty investment in high-speed railways, the nationwide double-track rail network and mass transit projects in Greater Bangkok.
Thanavath Phonvichai, vice-president for research at the University of the Thai Chamber of Commerce (UTCC), said the Thai economy is on course for stable growth over the next five years, thanks largely to the initiation of massive infrastructure developments.
The UTCC predicts that GDP will grow 4.5% in 2019, 4.8% in 2020, 4.6% in 2021 and 5% in 2022.
Growing exports, robust tourism, recovering farm prices and private investment prompted the university to raise its economic growth forecast to 4.6% for this year from 4.5% seen earlier.
Mr Thanavath said Thailand's export and tourism sectors have performed well, in line with the world's brighter economic prospects, while farm product prices have also improved, especially for five key crops: rice, tapioca, oil palm, corn and sugar cane.
Private investment has also started to recover, with government investment likely to accelerate in the second half of the year.
"Consumer confidence rose to the highest level in 64 months in August, clearly signalling that consumers have confidence to spend more," Mr Thanavath said.
The consumer confidence index in August rose to 83.2 from 82.2 in July and 81.3 in June, driven by the growing economy and higher prices for many farm products such as corn and tapioca.
"Consumer sentiment has improved significantly, particularly in the middle-income group, as indicated by higher car sales and new-home purchases," Mr Thanavath said. "People who live in manufacturing areas and tourist spots, in particular, have also enjoyed the benefits of growing exports and tourism."
The Commerce Ministry reported on Aug 22 that Thailand's exports grew for a 17th straight month in July, elevating performance in the first seven months to a seven-year high.
Customs-cleared exports rose 8.3% year-on-year in July, fetching US$20.2 billion (660 billion baht), after growing 8.2% in June and 11.4% in May.
Exports in baht terms rose by 4.1% from the same month of last year to 662.17 billion baht.
For the first seven months of 2018, Thai exports rose 10.6% to $146.23 billion.