The State Railway of Thailand (SRT) updates plans to revise the design for the Thai-Chinese high-speed rail Contract 4-5 at Ayutthaya station to avoid the World Heritage area. The auction is targeted for July to November 2026, with construction planned to start in 2027 and service expected to open in 2031. For Contract 4-1 at Don Mueang station, SRT warned it will take over work immediately if there are delays.
Mr. Anan Phonnimdaeng, Deputy Governor of the State Railway of Thailand (SRT), acting as SRT Governor, revealed after inspecting progress of the high-speed rail project that overall work on Contract 4-5 at Ayutthaya station, especially the redesign to avoid impact on the World Heritage area, remains within a construction budget of about 11 billion baht as approved by the Cabinet. The plan is to begin construction early 2027 and target opening between 2031 and 2032.
For Contract 4-5 covering Ban Pho to Phra Kaeo, a distance of 13.3 kilometers with a budget around 11 billion baht, the draft Terms of Reference (TOR) is expected to be completed by the end of May 2026. Public consultations are planned for June 2026, followed by bidding between July and November 2026. Contract signing is expected by late 2026, with construction starting early 2027. Civil works are projected to take about three years, finishing in 2030, with an additional year for system installation and testing, aiming for service launch in 2031.
Contract 4-5's redesign involves both architectural and engineering changes. The station center has been shifted slightly—less than 100 meters—from the original position to avoid overlapping with the old station building, which is a historic site. The new station structure is clearly separated from the old one, and the original plan for a large roof covering the old station has been canceled. These adjustments do not affect the Environmental Impact Assessment (EIA) as the route remains unchanged, and the station’s reduced size helps keep the budget within the original limit.
For construction, SRT plans parallel operations by dividing the site into two parts: about 7 kilometers that do not affect the World Heritage area, where track construction can begin immediately after the Notice to Proceed (NTP), and about 6 kilometers in sensitive zones for Ayutthaya station. Archaeological excavations will be conducted concurrently; any artifacts found will be recorded and relocated with the Fine Arts Department according to established procedures, similar to past projects.
Despite several constraints, SRT is confident that contractors remain interested in bidding, including the previous winning private groups who are willing to rejoin if project operation methods and budgets become clear. This is seen as a positive sign for advancing the project according to plan.
Regarding Contract 4-1 covering Bang Sue to Don Mueang stations, a joint structure with the 3-Airport Link high-speed rail project (Don Mueang-Suvarnabhumi-U-Tapao) currently held by Asia Erawan Company Limited (a CP Group concessionaire), delays persist. SRT has prepared contingency plans: if there is no clarity from the private sector by June to July 2026, it will propose to the project oversight committee to reclaim about 4 billion baht worth of track structure construction at Don Mueang station to execute internally to avoid impacting overall project timelines.
Meanwhile, the project faces legal and policy constraints, including ongoing Cabinet review of key issues such as the pay-as-you-go principle and operating rights fees. Without approval, the original contract conditions will apply, meaning the state reimburses joint venture costs after construction completion. Contract 4-1 also requires consideration by the project oversight committee under the Eastern Economic Corridor (EEC) law.
Mr. Anan addressed the energy price crisis, which has significantly affected SRT’s financial status. Originally, the organization assumed oil prices at 35 baht per liter, but current prices have risen to about 50 baht per liter, creating an immediate additional cost burden. Energy expenses represent about 30% of all variable costs, with an average daily oil consumption of 220,000 liters.
Due to this situation, SRT expects its liquidity shortfall, previously estimated at around 18 billion baht, to increase by at least 500 million baht. Nevertheless, SRT maintains a policy of fare stabilization during this period to avoid worsening the public’s cost of living. It plans to seek government budget support to compensate for losses and will closely monitor energy price trends until the fiscal year ends in September.
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