Collaborative Networked Organisations (CNOs) are increasingly recognised for their ability to harness cooperation and complementary competencies, outperforming indi- vidual efforts in pursuing business opportunities. However, the criticality of selecting the right long‐term partner for a CNO has been understated, especially considering the evolving landscape of sustainability perceptions. This research addresses the issue of time inconsistency within the context of sustainable CNO partner selection by employing the Fuzzy Analytical Hierarchical Process with the Technique for Order of Preference by Similarity to Ideal Solution. Time inconsistency refers to a situation where preferences or decisions change over different points in time, leading to inconsistencies in choices or actions. Specifically, the study focuses on a Swiss Manufacturing CNO, examining how the evaluation of potential partners' environmental criteria changes over time. The findings reveal the presence of time inconsistency in environmental criterion evaluation between two time periods. This inconsistency stems from the evolving perception of environmental conditions and the increasing social and governmental pressures sur- rounding environmental standards. As a consequence, improper partner choices in CNOs can be made, potentially undermining the collaborative's overall sustainability goals. The study sheds light on the importance of considering dynamic sustainability factors in partner selection for CNOs, emphasising the need for a more comprehensive and adaptive approach to secure fruitful and lasting collaborations