Politics
Siam Mayor Launches Infrastructure Levy, Property Bills Rise January 2027
Property owners in all five Siam districts will receive adjusted annual bills from January 2027 to fund road and drainage work under the new levy.
How we reported this
The mayor of Siam announced on 8 July 2026 that the Local Infrastructure Levy will begin collection in January 2027, applying to all residential and commercial properties across the city's five districts. The levy replaces the previous flat-rate maintenance charge and ties payments to property value assessments completed by the Siam Valuation Office in 2025.
The policy update follows the Siam City Council budget paper released in June 2026, which identified a shortfall of 85 million baht in routine road and drainage maintenance. Council documents state that revenue from the levy will cover 40 percent of that gap each year through 2029. Local government officials have scheduled public information sessions in each district starting 15 August 2026 to explain the new calculation method.
Changes to household and business costs
Residents will first notice the change when they receive their 2027 property tax statements in December 2026. For a typical single-family home in the Central District valued at 4.2 million baht, the annual levy component is projected at 6,300 baht, up from the prior 2,800 baht maintenance fee. Businesses along the Riverside commercial strip will see larger adjustments tied to floor area and assessed value.
The legislation states that payments can be made in two installments, with the first due by 31 January 2027 and the second by 30 June 2027. Local advocates note that households already receiving council rate rebates will continue to qualify for a 25 percent reduction on the new levy amount.
Timeline for visible service improvements
Work funded by the levy is scheduled to begin in the Northern District in March 2027, with resurfacing of 12 kilometres of local roads and replacement of 3.8 kilometres of drainage pipes. The government says the policy will produce completed projects in the remaining districts by December 2028. Council engineers have published a map of planned sites on the city website for residents to review before construction starts.
Further updates on exact billing amounts for individual properties will be mailed in October 2026 after final assessment reviews conclude. The Productivity Commission has found that similar value-based levies in other Thai municipalities have generated between 70 and 85 percent of projected revenue in their first two years of operation.