Discrepancies in blood typing is one of the major reasons in eliciting a transfusion reaction. These discrepancies can be avoided through detailed analysis for the blood typing. Here, we report a subgroup of blood group type-B in the ABO system. Donor's blood was analyzed by employing commercial antisera for blood grouping. The results of forward (known antisera) and reverse (known antigen) reaction were not complimentary. A detailed analysis using the standard protocols by American Association of Blood Banking revealed the blood type as a variant of blood group-B instead of blood group-O. This is suggestive of the fact that blood group typing should be performed with extreme care and any divergence, if identified, should be properly resolved to avoid transfusion reactions. Moreover, a major study to determine the blood group variants in Pakistani population is needed.