In earthquake-prone regions like Iceland, where an average of 500 earthquakes occurs weekly, modular buildings constructed according to EU standards face unique challenges. Despite their growing popularity, the impact of repeated earthquakes on the structural integrity of such buildings remains underexplored. This study focuses on evaluating the seismic performance of a 3D modular building, designed in compliance with EU standards, when subjected to multiple seismic sequences. Nonlinear time history analyses are conducted to simulate the effects of repeated earthquakes, specifically assessing inter-story drifts. The study also calculates damage indices and global ductility factors to quantify structural response under various seismic scenarios. Results reveal that the seismic sequence significantly influences the building’s performance, potentially exacerbating interstory drifts. These findings highlight the importance of considering the effects of repeated earthquakes in the design and evaluation of modular buildings, particularly in regions prone to seismic activity like Iceland. Incorporating such considerations into structural design practices and seismic codes is crucial to enhancing the resilience and safety of modular buildings in earthquake-prone areas.