In the Klungkung Regency Government, the percentage of construction project tenders with bids below 80% of the owner estimate during the period 2021-2025 reached 34.29%. Bids below 80% of the owner estimate have negatively affected construction project performance and client satisfaction. This study aims to analyze the effect of bids below 80% of the owner estimate on construction project performance and owner satisfaction, analyze the effect of construction project performance on owner satisfaction, analyze the mediating role of construction project performance in the relationship between bids below 80% of the owner estimate and owner satisfaction, and explore mitigation measures to minimize the negative impacts of bids below 80% of the owner estimate on construction project performance and owner satisfaction. This study employed a mixed-methods approach with an explanatory sequential design. The quantitative phase involved distributing questionnaires to project owners representing 30 construction projects in Klungkung Regency with bid prices below 80% of the owner estimate during the 2021-2025 period. Quantitative data were analyzed using SEM-PLS. The qualitative phase was conducted through FGD to formulate mitigation measures. The SEM-PLS results indicate that bids below 80% of the owner estimate have a significant negative effect on construction project performance and owner satisfaction in Klungkung Regency. Furthermore, construction project performance has a significant positive effect on owner satisfaction. Construction project performance also mediates the relationship between bids below 80% of the owner estimate and owner satisfaction through complementary partial mediation. The FGD results identified ten mitigation measures focusing on strengthening technical control, monitoring project implementation, evaluating project schedules, implementing the Construction Safety Management System, enhancing coordination, and improving responsiveness to owner instructions