In this study, the circularity of multifunction photocopier toner bottles is evaluated using Life Cycle Simulation (LCS) focusing on component remanufacturing and the effect of circularity on life cycle cost and CO2 emissions is quantified. LCS, which executes discrete event simulations, can evaluate the circularity of the entire life cycle of products. A what-if analysis is undertaken by varying the parameters, including the maximum remanufacturing count, number of remanufacturing sites, collection rate, and compatibility between new and old generations of photocopiers. This study determines that the compatibility of new and old copier models is critically important for increasing circularity and reducing CO2 emissions and life cycle costs. CO2 emissions and life cycle costs are reduced to 42% and 87%, respectively, comparing to the situation where the bottles are not remanufactured at all. However, some difficulties in obtaining the required data from the manufacturer made it difficult to evaluate circularity.