(D)ifferential scanning calorimetry is employed to investigate the cold flow property of a series of fuel mixtures prepared from fast pyrolysis bio-oil, crude glycerol, methanol, and/or biochar. Bio-oil alone has a melting peak temperature (T-MP) of -21.9 degrees C that may lead to difficulties in practical applications under extreme cold weather conditions. Bio-oil water-soluble fraction (WSF) is even more problematic as its TMP is -8.7 degrees C. The results show that these problems can be alleviated or even eliminated by mixing various formulated crude glycerols (FCGs) with bio-oil or WSF. The T-MP of FCG/methanol/bio-oil. (FCGMB) blends significantly decreased from -21.9 to -38.1 degrees C. Similar phenomena were also seen for the FCG/WSF (FCGWSF) blends, with decreases in TMP from -8.7 to -32.0 degrees C. Water can worsen the cold flow properties of FCGMB and FCGWSF blends. However, other components in FCGs can lower the TMP and hence improve the cold flow properties of these fuel mixtures (with the effectiveness in the order of NaCI > NaOH > methanol > glycerol > soap due to solvation effect). The presence of biochar has a limited effect on the cold flow property of the slurry fuels, leading to a decrease of merely 4 degrees C in the T-MP at a 20% biochar loading level.