This study evaluates the financial impacts of implementing construction waste reduction measures using two construction projects in Asker, Norway, as case studies. The research analyses the effectiveness of a municipal bonus scheme designed to incentivise waste minimisation and recycling. Eight waste reduction measures were assessed for their cost implications and waste reduction potential, including modular construction, reuse of materials, and on-site waste management practices. The measures led to a 23% reduction in on-site waste and more than doubled recycling rates for the two projects, without incurring significant costs for the contractor. The modular roof was the most cost-effective measure, while time-intensive activities were the primary cost drivers. The study highlights the importance of clear definitions, collaborative procurement practices, and experience transfer in achieving cost-effective waste reduction. Well-structured incentive schemes can play a pivotal role in promoting circular construction practices and reducing the environmental footprint of building projects. The findings are limited by reliance on contractor estimates and exclusion of some implemented measures due to data constraints and complexity. Nonetheless, the study provides useful insights into cost-effective waste reduction strategies.