Despite the fact that many organizations must manage frequently multiple paradoxes in their operations, extant paradox studies have under-researched the phenomenon of a knotted paradox that emerges when actors navigate in conditions of contradicting demands, which stem from several paradoxes simultaneously. In this study, we explore the knotted paradox of coopetition for sustainability, a process in which competitors cooperate to address sustainability challenges, and examine the interplay between its intensity, balance, and outcome. The findings of a quantitative study conducted among organizational actors in the housing sector demonstrate that coopetition intensity has a significant yet complex impact on sustainability outcomes. In the relationship characterized by an inverted U-shaped curve, an increase in coopetition intensity and balance leads to an increase in sustainability outcomes, but only until a specific limit, after which sustainability outcomes decrease with further intensification of coopetition. The findings indicate that coopetition balance and sustainability balance do not have a significant relationship. The study provides insights for managers on how coopetition in different conditions can contribute to corporate sustainability. The study demonstrates that coopetition and sustainability can be knotted successfully, although the intensity of competing demands and the balance between them need to be cautiously managed.