According to the Government of India, linking Aadhaar with the delivery of welfare schemes has saved nearly INR 2,73,093 crore till March 2022 due to, apparently, the removal of duplicate/​fake beneficiaries and plugging of leakages, etc. What is the overall impact of Aadhaar on welfare delivery? We try to understand this through a case study of MGNREGA in Jharkhand. Surveying nearly 3,000 workers in eight villages in Jharkhand to assess both the costs and benefits of linking MGNREGA with Aadhaar, the paper focuses on its impact on errors of inclusion and exclusion.