COVID-19-related critical and acute illness are associated with an increased risk of venous thromboembolism (VTE). These evidence-based recommendations of the American Society of Hematology (ASH) are intended to support patients, clinicians, and other healthcare professionals in decisions about the use of anticoagulation for thromboprophylaxis in patients with COVID-19-related critical illness, acute illness, and those being discharged from the hospital, who do not have suspected or confirmed VTE. ASH formed a multidisciplinary panel, including three patient representatives, and applied a conflicts of interest management policy to minimize potential bias. The Michael G. DeGroote Cochrane Canada and MacGRADE Centres at McMaster University supported the guideline development process, including performing systematic evidence reviews (up to June 2023). The panel prioritized clinical questions and outcomes according to their importance for clinicians and patients. The panel used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to assess certainty of the evidence and make recommendations, which were subject to public comment. This is an executive summary of three updated recommendations that have been published which concludes the living phase of the guidelines. For critically ill patients with COVID-19, the panel issued conditional recommendations in favor of (a) prophylactic-intensity over therapeutic-intensity anticoagulation and (b) prophylactic-intensity over intermediate-intensity anticoagulation. For acutely ill patients with COVID-19, conditional recommendations were made in favor of (a) prophylactic-intensity over intermediate-intensity anticoagulation and (b) therapeutic-intensity over prophylactic-intensity anticoagulation. The panel also issued a conditional recommendation against the use of post-discharge extended pharmacologic thromboprophylaxis. These three conditional recommendations were made based on low or very low certainty in the evidence, underscoring the need for additional, high-quality randomized controlled trials in patients with COVID-19-related illness.