Objective: In the United Kingdom, the coronavirus disease 2019 (COVID-19) pandemic has led to the cessation of elective surgery. However, there remains a need to provide urgent and emergency cardiac and thoracic surgery as well as to continue time-critical thoracic cancer surgery. This study describes our early experience of implementing a protocol to safely deliver major cardiac and thoracic surgery in the midst of the pandemic. Methods: Data on all patients undergoing cardiothoracic surgery at a single tertiary referral center in London were prospectively collated during the first 7 weeks of lockdown in the United Kingdom. A comprehensive protocol was implemented to maintain a COVID-19–free environment including the preoperative screening of all patients, the use of full personal protective equipment in areas with aerosol-generating procedures, and separate treatment pathways for patients with and without the virus. Results: A total of 156 patients underwent major cardiac and thoracic surgery over the study period. Operative mortality was 9% in the cardiac patients and 1.4% in thoracic patients. The preoperative COVID-19 protocol implemented resulted in 18 patients testing positive for COVID-19 infection and 13 patients having their surgery delayed. No patients who were negative for COVID-19 infection on preoperative screening tested positive postoperatively. However, 1 thoracic patient tested positive on intraoperative bronchoalveolar lavage. Conclusions: Our early experience demonstrates that it is possible to perform major cardiac and thoracic surgery with low operative mortality and zero development of postoperative COVID-19 infection.