Boiling heat transfer experiments were performed in a 2.98-mm inside-diameter horizontal tube with a two-component mixture of 50150 ethylene glycol and water. The data were compared with existing results from three single-component fluids under similar boiling conditions. Boiling heat transfer in small channels with the single-component fluids exhibited a nucleation dominant region that is considerably more extensive than found in larger diameter tubes. Data for the 50150 ethylene glycol/water mixture were similar in this regard to the single-component fluids; differences occurred with respect to heat transfer rates, extent of transition boiling, critical heat flux, and flow stability. Based on these data comparisons, we developed a concept for dividing flow boiling into its three regions. Using this division, we developed a new general correlation for the nucleation-dominant region based on Boiling and Weber numbers. The correlation is specific to nucleation-dominant flow boiling in small channels, and it provides good predictions of the data from all four fluids: Refrigerants 12 and 134a, water, and 50/50 ethylene glycol/water mixture.