Bangkok authorities have announced stricter exhaust-smoke standards for diesel vehicles, effective 1 November 2025, marking a significant regulatory step in Thailand’s transition toward electric mobility and its broader climate policy agenda. The measure complements ongoing electric vehicle (EV) incentives and the forthcoming Climate Change Bill to be passed into Climate Change Act, which is expected to provide Thailand with its first comprehensive legal framework for greenhouse gas regulation.
The new regulation primarily targets older diesel vehicles, particularly those manufactured before compliance with Euro 5 emission standards. The permissible exhaust-smoke opacity threshold will be reduced from 30% to 20%, significantly tightening enforcement against high-emission engines.
Vehicles found in violation will face:
- Fines of up to THB 4,000, and
- A mandatory re-inspection process.
If a vehicle fails to comply following re-inspection, authorities may prohibit its use for up to 30 days. This enforcement mechanism signals a shift from symbolic regulation toward active compliance monitoring, particularly in urban areas facing persistent air pollution challenges.
Thailand continues to position itself as Southeast Asia’s largest EV market. Between January and July 2025, EV registrations reached approximately 66,000 units, nearly matching the total for all of 2024. The government has reaffirmed its target for 30% of domestic vehicle production to be zero-emission by 2030, equivalent to more than 700,000 vehicles annually based on current output.
To support this objective, Thailand offers extensive incentives under the EV3.0 and EV3.5 schemes, including:
- Excise tax reductions,
- Import duty exemptions, and
- Direct consumer and manufacturer subsidies.
EV3.5 extends support through 2027 and continues to require automakers importing battery electric vehicles (BEVs) to commit to local assembly within defined timelines.
To strengthen Thailand’s role as a regional EV manufacturing hub, the government has introduced export-linked incentives, allowing each exported EV to count as 1.5 units toward local production quotas. This policy is expected to significantly increase EV exports from 12,500 units in 2025 to approximately 52,000 units in 2026.
In parallel, Thailand will debut its EV brand in late 2025 through a partnership with Chery Automobile, with production based in Rayong Province.
These developments align with Thailand’s forthcoming Climate Change Bill, currently in its final drafting stage. The legislation is expected to introduce emissions reduction mechanisms, a national climate fund, and potential carbon market tools, reinforcing Thailand’s commitments to carbon neutrality by 2050 and net-zero emissions by 2065.