Background and Objectives  Emergency situations often elicit a generous response from the public. This occurred after attacks on the US on September 11, 2001 when many new blood donors lined up to donate. This study was performed to compare return rates for first time donors (FTD) after September 11th, 2001 to FTD during a comparable period in 2000. Materials and Methods  A total of 3315 allogeneic whole blood donations from FTD at a regional blood centre were collected between September 11th and 30th, 2001. Subsequent donations by the FTD before March 31, 2002 were reviewed. This (test) group was compared to 1279 FTD (control group) donating during the same time period in September 2000 and to their return rate in the subsequent 6 months. Results  Following September 11, 2001, 1087/3315 (32·8%) FTD returned by March 31, 2002. This return rate was similar to the control group [427/1279 (33·4%)]. The deferral rate during the donor screening process for the control group was significantly higher than the deferral rate for the September 11–30, 2001 group (P < 0·01). The odds of an individual FTD returning increased with age, and the chance of a female donor returning was 1·13 times higher than a male (P = 0·06). There was a carryover effect after September 11, 2001 too. Conclusion  A national emergency, September 11, 2001, inspired people to donate blood for the first time. However, the proportion of return donations amongst them was not increased. Females and males in certain age groups were more likely to become repeat donors due to the residual effect of September 11, 2001. Additional efforts are needed to retain eligible FTD in donor pools.