The paper introduces a comprehensive and integrated tool developed to analyse socio-economic impacts of floods due to sea-level rise (SLR) on coastal cities, and presents the outcomes of a case study application in Bangkok, Thailand. The study aimed to capture a macro picture of floods to present an overview of the severity of flooding under the projected SLR conditions. A physically-based distributed flood model, which combines surface and river flow, was adopted to simulate the flood scenarios due to different magnitudes of sea-level rise. The input rainfalls and upstream boundary conditions of a worst-case flood event of 1995 were considered as the baseline for the modelling, based on the available records of rainfall and water-level data sets of the last three decades. The outcomes of the case study present a detailed picture of floods and their socio-economic impacts in Bangkok City under the worst projected SLR scenarios in the 21st century. The simulated results show that for baseline conditions of 1995, the overall inundation area in Bangkok may increase up to 26% in 2050 due to a SLR of 32 cm, and to 81% in 2100 due to 88 cm SLR, compared to the extent of flood inundation in 1995. The number of flood affected buildings is likely to increase by a factor of 1.5 in the 75 years from 2025 to 2100.