SRT to seek Cabinet approval for three-airport high-speed rail contract changes
Thailand’s three-airport high-speed rail PPP is moving towards a revised payment model and staged ARL concession fees, with a draft amended contract targeted for Cabinet consideration in June and signing in July 2026.
- The State Railway of Thailand (SRT) will ask the Cabinet to approve changes to the project's payment structure, shifting the state's investment to installments based on construction progress and allowing the private partner to pay its concession fee in seven annual installments.
- These amendments are the result of negotiations that began after the COVID-19 pandemic impacted passenger forecasts, leading the private partner, Asia Era One Co., Ltd., to seek compensation.
- The SRT is targeting a July 2026 contract signing to prevent delays to the interconnected Thai-Chinese high-speed rail project, with the three-airport line now projected to open in 2032.
The high-speed rail project linking three airports (Don Mueang, Suvarnabhumi and U-Tapao) is a public-private partnership (PPP) scheme.
The investment contract was signed between the State Railway of Thailand (SRT) and Asia Era One Co., Ltd., in which the Charoen Pokphand Group (CP Group) is the major shareholder, on October 24, 2019, after the company won the tender by proposing the lowest state co-investment request of THB117.226 billion.
After that, the Covid-19 outbreak affected the project as passenger forecasts fell, and the private partner sought compensation.
The Cabinet approved the compensation measures on October 19, 2021, under the government of Gen Prayut Chan-o-cha, and negotiations to amend the contract have continued through the administrations of Srettha Thavisin, Paetongtarn Shinawatra and Anutin Charnvirakul.
However, the draft contract amendments have still not been approved.
Overall, the public has missed out on the opportunity to use this high-speed rail line for more than six years.
Anan Phonimdaeng, deputy governor of the State Railway of Thailand and acting governor, spoke after the SRT board meeting on February 18, 2026.
He said the board had acknowledged progress on the three-airport high-speed rail project, and that the SRT has submitted a report seeking approval to revise the project’s underlying principles to the Eastern Economic Corridor Office (EECO), ahead of a proposal to the Cabinet.
The Cabinet will be asked to consider amendments to the PPP principles, in line with the earlier resolution of the Eastern Economic Corridor Policy Committee.
The key points of the proposed revisions include:
- The payment method for the state’s Public Investment Cost (PIC. Previously, once the private partner began operating the high-speed rail service, the state would pay a total of THB149.65 billion. This would be adjusted to instalment payments based on work progress as certified by the SRT, capped at no more than THB120 billion.
- The schedule for paying the concession fee under the Airport Rail Link (ARL) investment rights. The private partner would pay the THB10.67109 billion concession fee in seven equal annual instalments, with the first instalment due on the date the amended contract is signed.
“Revising the underlying principles is now considered complete on the SRT’s side. We have concluded with the private partner and submitted it to the EECO. After that, the EECO will forward it to the Cabinet for approval of the principal changes, based on the principles already considered by the Eastern Economic Corridor Policy Committee, namely, shifting to a build-and-pay-as-you-go method and splitting the ARL concession payments.”
While awaiting consideration of the principal changes, the SRT will also consult the Office of the Attorney-General to prepare the “final draft contract” before signing the amended contract with the private partner.
The SRT has set out the following working timeline:
- Submit the draft contract to the Cabinet for consideration in June 2026
- Sign the contract in July 2026
- Issue the Notice to Proceed (NTP) within 30 days, or in August 2026
- Construction period of five years
- System testing for a further six months
- Expected opening in 2032
Because the three-airport high-speed rail project shares civil works with the Thai–Chinese high-speed rail project on the Bang Sue–Don Mueang section, the contract amendment must be concluded to avoid affecting the Thai–Chinese project’s civil works.
Under the conditions for the shared civil works on that section, Asia Era One Co., Ltd. is responsible for construction.
The latest timeline is therefore considered appropriate.
If the contract cannot be signed within the planned timeframe in July 2026, the SRT will need to submit the matter to the Cabinet to consider changing the scope of work.
This would require the SRT to take back and construct the shared civil works under Contract 4-1 (Bang Sue–Don Mueang) itself, to avoid affecting the overall construction of the Thai–Chinese high-speed rail project.
The SRT assesses that the proposed timeline aligns with Contract 4-5 (Ban Pho–Phra Kaew), which is currently in the process of finalising the Ayutthaya station design adjustments and preparing to open bidding to appoint contractors.
