For a study, researchers sought to determine that infection with the coronavirus disease 2019 (COVID-19) before or shortly after procedures increases mortality, but they make no recommendations for when to start treatment following diagnosis. They attempted to establish the most secure window for major surgical operations in COVID-19-positive patients. From the Veterans Affairs COVID-19, Shared Data Resource, high-risk operations between January 2020 and May 2021 were identified. COVID-19 positive patients (n=938) and negative controls (n=7,235) were precisely matched using Current Procedural Terminology (CPT) codes. The continuous variable of time effects was computed, and the results were then grouped into 2-week intervals. The main result was postoperative mortality for all causes at 90 days. When the operation was carried out within 9 weeks or more of a positive test, the 90-day mortality rate was similar in both cases and controls; however, it was significantly higher in cases compared to controls when it was carried out within 7 to 8 weeks (12.3% vs. 4.9%), 5 to 6 weeks (10.3% vs. 3.3%), 3 to 4 weeks (19.6% vs. 6.7%), and 1 to 2 weeks (24.7% vs. 7.4%) from diagnosis. About 90-day mortality was 16.6% for cases versus 5.8% for controls among patients who had surgery within 8 weeks of diagnosis (P<0.001). They examined the interactions between case status and any symptom in this group (P=0.93) and between case status and either respiratory symptoms or fever (P=0.29), none of which was statistically significant. In contrast to CPT-matched controls without a COVID-19 diagnosis, patients with major procedures within 8 weeks of a positive test have significantly increased postoperative 90-day mortality. This was true regardless of the patient’s presenting symptoms.