The t(1;19) in B-lineage ALL is classically associated with a FAB L1/L2 phenotype and the expression of cIg. Recent reports have demonstrated immuno-phenotypic and molecular heterogeneity among cases demonstrating apparently identical karyotypic abnormalities. We report 5 cases of t(1;19) with cytological features resembling an L3 (Burkitt-like) phenotype, suggesting that accurate assessment of these cases requires detailed correlation of cytological, immunological and molecular characteristics.