The Asian Development Bank (ADB) has sharply downgraded Thailand’s 2025 GDP growth forecast to 2.0 percent, a cut of 0.8 percentage points from its April projection of 2.8 percent, according to the September 2025 Asian Development Outlook (ADO).
For 2026, the outlook deteriorated further, with growth now projected at just 1.6 percent, down 1.3 percentage points from April’s estimate of 2.9 percent.
On inflation, forecasts were also lowered.
Consumer prices are expected to rise only 0.5 percent in 2025, compared with 1.0 percent previously, before slowing further to 0.8 percent in 2026.
Persistently weak price growth signals subdued demand, though it provides policymakers with space to maintain accommodative measures.
Thailand’s growth outlook is now the weakest among Southeast Asia’s major economies.
Thailand’s downgraded outlook leaves it at the bottom of the region’s growth league.
Vietnam leads with a 2025 forecast of 6.7 percent, followed by the Philippines at 5.6 percent, Indonesia at 4.9 percent, and Malaysia at 4.3 percent. Thailand’s 2 percent is well below the Southeast Asia average of 4.3 percent.
On inflation, Thailand’s 2025 forecast of 0.5 percent is the lowest in the region, reflecting subdued demand.
By comparison, Vietnam is projected at 3.9 percent, the Philippines at 1.8 percent, Indonesia at 1.7 percent, and Malaysia at 1.8 percent.
While low inflation provides policy space, it also highlights the lack of momentum in Thailand’s economy relative to its peers.
See also: Thailand’s Economy 2025: GDP, FDI & Key Industries
GDP growth forecasts (% per year)
| 2025 | 2026 | |||||
| Apr | Sep | Change | Apr | Sep | Change | |
| Southeast Asia | 4.7 | 4.3 | -0.4 | 4.7 | 4.3 | -0.5 |
| Vietnam | 6.6 | 6.7 | 0.1 | 6.5 | 6.0 | -0.5 |
| Indonesia | 5.0 | 4.9 | -0.1 | 5.1 | 5.0 | -0.1 |
| Philippines | 6.0 | 5.6 | -0.4 | 6.1 | 5.7 | -0.4 |
| Thailand | 2.8 | 2.0 | -0.8 | 2.9 | 1.6 | -1.3 |
| Malaysia | 4.9 | 4.3 | -0.6 | 4.8 | 4.2 | -0.6 |
Inflation forecasts (% per year)
| 2025 | 2026 | |||||
| Apr | Sep | Change | Apr | Sep | Change | |
| Southeast Asia | 3 | 2.5 | -0.5 | 2.8 | 2.7 | -0.1 |
| Vietnam | 4 | 3.9 | -0.1 | 4.2 | 3.8 | -0.4 |
| Indonesia | 2 | 1.7 | -0.3 | 2 | 2 | 0.0 |
| Philippines | 3 | 1.8 | -1.2 | 3 | 3 | 0.0 |
| Thailand | 1 | 0.5 | -0.5 | 1.1 | 0.8 | -0.3 |
| Malaysia | 2.5 | 1.8 | -0.7 | 2.5 | 2.2 | -0.3 |