Calcium phosphate bone cements are materials used mainly to augment bone and promote the regeneration of the bone tissue. Calcium phosphate cements set at body temperature, so they can be easily given additional functionality, such as delivery of biologically active substances to the defect site. As these materials set upon application, their application is time sensitive. One way to improve the ease handling of calcium phosphate cements is to formulate premixed compositions. In this study we investigate the properties of premixed cementing calcium phosphate pastes based on α-tricalcium phosphate (α-TCP) and glycerol. The setting reactions in these pastes start upon implantation as the inert paste liquid (glycerol) is gradually displaced by water from the surrounding fluids. Soluble sodium or potassium phosphate salts are used to improve the setting of these pastes. We evaluated mechanical strength, setting, phase composition, and anti-washout properties of the premixed pastes. Particular attention was given to the choice of additives used to promote the setting.