Provided herein are systems and methods for analyzing blood samples, and more specifically for performing a basophil analysis. In one embodiment, the systems and methods include: (a) staining a blood sample with an exclusive cell membrane permeable fluorescent dye; and then (b) using measurements of light scatter and fluorescence emission to distinguish basophils from other WBC sub-populations. In one embodiment, the systems and methods include performing a basophil cluster analysis of the blood sample, based on the combination of light scatter and fluorescence measurements.