In this paper, we evaluate decarbonization opportunities for the power and industry sectors in Thailand by carbon capture and storage (CCS). Stationary CO 2 sources from the power sector include coal-fired, natural gas-fired and waste-to-energy power plants. Stationary CO 2 sources from the industry sector include cement factories, refineries, iron and steel mills, petrochemical plants, and natural gas processing plants. Potential sites for subsurface CO 2 storage include oil fields, gas fields and saline aquifers in four offshore sedimentary basins (Songkhla, Pattani, Chumpon, Malay) and six onshore sedimentary basins (Fang, Phetchabun, Phitsanulok, Suphan Buri, Kamphaeng Saen, and Khorat). Data used in this study come from an extensive review of peer-reviewed journals, conference proceedings, and published reports. Results show that stationary CO 2 emission from the two sectors is 143 Mtpa consisting of 79 Mtpa from power plants and 64 Mtpa from industrial plants. The biggest CO 2 emission in the power sector comes from natural gas-fired power plants whereas that from the industry sector comes from cement factories. There is a total of 79 Gt of subsurface CO 2 storage capacity (mid case scenario) in Thailand, which is enough to store 554 years of CO 2 emission from stationary sources. Of this, 77.6 Gt (98%) comes from saline aquifers, 1.7 Gt (2%) from gas reservoirs, and only 0.05 Gt (<1%) from oil reservoirs. Therefore, saline aquifers are the most important sites for subsurface CO 2 storage. We propose using CCS clusters to reduce the overall project cost by using economies of scale. In a CCS cluster, multiple CO 2 sources are mapped to a common CO 2 sink by sharing the same CO 2 capture, transport, and injection network. A CO 2 source-sink mapping exercise results in the identification of six CCS clusters. For Cluster I, we propose a CCS demonstration project by capturing CO 2 emitted from cement factories near the city of Saraburi and transporting it to the nearby Sirikit oil field for CO 2 -enhanced oil recovery. This project can potentially recover 29 MMbbl of incremental oil. For Cluster II, CO 2 emitted from natural gas-ired power plants around Bangkok and petrochemical plants in Rayong is captured and stored in saline aquifers in the nearby Khorat Basin. For all other CCS clusters, emitted CO 2 can be stored in saline aquifers within a 200 km distance. However, detailed characterization of saline aquifers in Thai sedimentary basins such as caprock integrity, reservoir connectivity, net-to-gross etc., is required to materialize these CCS projects. • Stationary CO 2 emission in Thailand is 79 Mtpa from the power sector and 64 Mtpa from the industry sector. • There is 79.3 Gt of mid CO 2 storage capacity in Thailand, which is enough to store 567 years of CO 2 emission from stationary sources. • There is CO 2 -EOR/EGR potential 174 MMbbl from 53 oil and gas fields in Thailand. • However, most Thai gas fields are still under primary depletion and therefore not ready for CO 2 storage. • A source-sink mapping exercise has identified six CCS clusters where CO 2 sources within a cluster are mapped to CO 2 sinks within the same cluster for permanent storage.