The postural stability on a passive lower extremity exoskeleton is important in preventing the falls at workplaces. The aim of this study was to assess the maximal reaching distances (functional reach test) and the weight distributions while reaching forward, backward, and side directions with and without the Chairless Exoskeleton (CEX) at different height settings (NO CEX, CEX HIGH, and CEX LOW). Twenty participants engaged in randomized tasks, and kinematic and ground reaction force (GRF) data were collected. CEX use showed no impact on anterior reaching but significantly reduced posterior (p = 0.001) and lateral (p < 0.001) reaching distances. CEX height had no significant effect. Anterior reaching GRF on the feet was 76% and 75% of body weight with CEX HIGH and CEX LOW. In posterior reaching, GRF on the feet was 19% and 24%, and in lateral reaching, it was 42% and 48%. In conclusion, even without CEX, posterior reaching is limited, and the CEX exacerbates this limitation, primarily due to restricted knee motion. This underscores the need for design enhancements and cautionary measures for workers before exoskeletons are deployed in the workplace.