Call back as a procedure to report post donation symptoms or illness by donors has been established since 2009 in Iranian Blood Transfusion Organization (IBTO). During the first phase of COVID-19 outbreak, all blood donors were requested to report any respiratory infection symptoms after donation . The study investigated the callback data of COVID-19 in Tehran Blood Center during the first 3 months of the outbreak in Iran . The purpose of this study was to estimate the frequency of post donation COVID-19 related call back reports and determine its implications for blood donors and patients . A telephone interview was conducted with donors who had reported COVID-19 symptoms . Some questions were asked to evaluate donor's health at the time of blood donation . The donors categorized into three groups: laboratory-confirmed, suspected, and COVID-19 irrelevant based on their answers . In cases that the blood component obtained from a laboratory-confirmed donor had been released, the hospital was notified and asked to follow up the recipient for COVID-19 . The results showed 30 donors (0.08 %) had callback related to COVID-19 and 76.63% of the obtained component was disposed . The results also showed that only one donor had a laboratory-confirmed result with the RBC unit processed from her whole blood released for transfusion . The RBC unit recipient did not show any signs or symptoms of infection during a 46-day follow-up . Concluded that callback system was effective to remove most of the components obtained from the donors who reported to be COVID-19 suspected or confirmed . Moreover, the result did not support virus transmission through blood transfusion.