The Treasury Department is preparing a new round of land and building appraisal prices for 2027–2030, which will take effect on 1 January 2027, replacing the current appraisal used since 2023. The amended prices are expected to be finalised by 1 December 2026 and will continue to serve as the tax base for land and building tax assessments nationwide.
Land prices along mass transit lines in Bangkok and surrounding areas are expected to increase by no more than 10% on average, reflecting ongoing economic slowdown despite improved accessibility from expanded rail networks. Appraisals are conducted every four years and take into account economic conditions, infrastructure development, environmental factors, and actual transaction prices in each locality.
The Treasury Department has also indicated an intention to narrow the gap between appraisal prices and market prices. Under the current framework, appraisal values are estimated to be 30–40% below market prices. For the upcoming appraisal cycle, the department aims to reduce this discrepancy to no more than 20%, with adjustments implemented gradually to mitigate sudden tax burdens on property owners.
Under existing appraisal prices, the highest land value in Bangkok is Wireless Road at THB 1 million per square wah, while the lowest is in Bang Khunthian district at THB 500 per square wah. Provincially, the highest valuation is on Prachathipat Road, Songkhla (THB 400,000 per square wah), and the lowest is in Omkoi district, Chiang Mai (THB 25 per square wah).
Property owners, developers, and investors should anticipate gradual increases in land and building tax exposure beginning in 2027, particularly in transit-oriented areas. Early review of asset portfolios and tax planning strategies may help manage the impact of higher appraisal values, especially where market prices significantly exceed current Treasury valuations.