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Tectonic activities initiate numerous Earth phenomena, including natural hazards due to the activity of the Palu – Koro fault. It caused 28 September 2018 disaster with numerous casualties. Active faults, as this, need deformation monitoring. The majority of studies employed Synthetic Aperture Radar (SAR) technology for this purpose, which is capable of observing changes in position up to millimeters. A deformation map is usually derived from Small Baseline Subset Interferometric SAR (SBAS-InSAR) technique. It was further developed as P-SBAS allowing an effective computation of large SAR data sequences. The purpose of this study was to determine the distribution and rate of deformation velocity in Palu City using Sentinel-1 data from 2018 (after the earthquake) until 2021. The spatial distribution of deformation was analyzed to determine negative impacts that are likely to occur in the long term. All data were processed using cloud-based processing, i.e., the Geohazard Exploitation Platform (GEP). GEP is very helpful in terms of processing speed and storage availability rather than processing using a personal computer. This processing produced a deformation value at 20363 coordinate points, where 12317 was within Palu city. Some areas had no deformation rate because coherence was less than 0.8. The maximum negative line-of-sight (LoS) deformation value was -1.5 cm/year in South Palu Sub-district with the maximum positive was 2.4 cm/year in Mantikulore. On the west side of Palu, there was a clear boundary between uplifted areas and subsidence. Based on the Disaster Hazard Zone map of Palu City and its surroundings, the area is a part of the Palu Koro fault line. The central part of Palu City experienced subsidence, while on the east side, there were either uplift and subsidence. The impact of continuous deformation includes destruction of residential buildings and infrastructure, triggering landslides and flash floods, causing tidal flooding, and unclear land boundaries. A review of the regional development plan is therefore needed to mitigate the negative impact. [ABSTRACT FROM AUTHOR]